Merging upstream version 1.68.2+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

25 files changed, 1689 insertions, 309 deletions

diff --git a/compiler/rustc_codegen_ssa/Cargo.toml b/compiler/rustc_codegen_ssa/Cargo.toml
index 345174fb5..0d2d2ec68 100644
--- a/compiler/rustc_codegen_ssa/Cargo.toml
+++ b/compiler/rustc_codegen_ssa/Cargo.toml
@@ -15,7 +15,7 @@ tracing = "0.1"
 libc = "0.2.50"
 jobserver = "0.1.22"
 tempfile = "3.2"
-thorin-dwp = "0.3"
+thorin-dwp = "0.4"
 pathdiff = "0.2.0"
 serde_json = "1.0.59"
 snap = "1"
@@ -27,6 +27,7 @@ rustc_arena = { path = "../rustc_arena" }
 rustc_ast = { path = "../rustc_ast" }
 rustc_span = { path = "../rustc_span" }
 rustc_middle = { path = "../rustc_middle" }
+rustc_type_ir = { path = "../rustc_type_ir" }
 rustc_attr = { path = "../rustc_attr" }
 rustc_symbol_mangling = { path = "../rustc_symbol_mangling" }
 rustc_data_structures = { path = "../rustc_data_structures" }
@@ -43,6 +44,6 @@ rustc_session = { path = "../rustc_session" }
 rustc_const_eval = { path = "../rustc_const_eval" }
 
 [dependencies.object]
-version = "0.29.0"
+version = "0.30.1"
 default-features = false
 features = ["read_core", "elf", "macho", "pe", "unaligned", "archive", "write"]
diff --git a/compiler/rustc_codegen_ssa/src/back/archive.rs b/compiler/rustc_codegen_ssa/src/back/archive.rs
index 58558fb8c..d3cd085cf 100644
--- a/compiler/rustc_codegen_ssa/src/back/archive.rs
+++ b/compiler/rustc_codegen_ssa/src/back/archive.rs
@@ -124,7 +124,7 @@ fn try_filter_fat_archs(
 ) -> io::Result<Option<PathBuf>> {
     let archs = archs.map_err(|e| io::Error::new(io::ErrorKind::Other, e))?;
 
-    let desired = match archs.iter().filter(|a| a.architecture() == target_arch).next() {
+    let desired = match archs.iter().find(|a| a.architecture() == target_arch) {
         Some(a) => a,
         None => return Ok(None),
     };
diff --git a/compiler/rustc_codegen_ssa/src/back/link.rs b/compiler/rustc_codegen_ssa/src/back/link.rs
index fe2e4b36c..34e042376 100644
--- a/compiler/rustc_codegen_ssa/src/back/link.rs
+++ b/compiler/rustc_codegen_ssa/src/back/link.rs
@@ -11,7 +11,7 @@ use rustc_metadata::find_native_static_library;
 use rustc_metadata::fs::{emit_wrapper_file, METADATA_FILENAME};
 use rustc_middle::middle::dependency_format::Linkage;
 use rustc_middle::middle::exported_symbols::SymbolExportKind;
-use rustc_session::config::{self, CFGuard, CrateType, DebugInfo, LdImpl, Lto, Strip};
+use rustc_session::config::{self, CFGuard, CrateType, DebugInfo, LdImpl, Strip};
 use rustc_session::config::{OutputFilenames, OutputType, PrintRequest, SplitDwarfKind};
 use rustc_session::cstore::DllImport;
 use rustc_session::output::{check_file_is_writeable, invalid_output_for_target, out_filename};
@@ -208,16 +208,16 @@ pub fn link_binary<'a>(
     Ok(())
 }
 
+// Crate type is not passed when calculating the dylibs to include for LTO. In that case all
+// crate types must use the same dependency formats.
 pub fn each_linked_rlib(
-    sess: &Session,
     info: &CrateInfo,
+    crate_type: Option<CrateType>,
     f: &mut dyn FnMut(CrateNum, &Path),
 ) -> Result<(), errors::LinkRlibError> {
     let crates = info.used_crates.iter();
-    let mut fmts = None;
 
-    let lto_active = matches!(sess.lto(), Lto::Fat | Lto::Thin);
-    if lto_active {
+    let fmts = if crate_type.is_none() {
         for combination in info.dependency_formats.iter().combinations(2) {
             let (ty1, list1) = &combination[0];
             let (ty2, list2) = &combination[1];
@@ -230,27 +230,23 @@ pub fn each_linked_rlib(
                 });
             }
         }
-    }
-
-    for (ty, list) in info.dependency_formats.iter() {
-        match ty {
-            CrateType::Executable
-            | CrateType::Staticlib
-            | CrateType::Cdylib
-            | CrateType::ProcMacro => {
-                fmts = Some(list);
-                break;
-            }
-            CrateType::Dylib if lto_active => {
-                fmts = Some(list);
-                break;
-            }
-            _ => {}
+        if info.dependency_formats.is_empty() {
+            return Err(errors::LinkRlibError::MissingFormat);
         }
-    }
-    let Some(fmts) = fmts else {
-        return Err(errors::LinkRlibError::MissingFormat);
+        &info.dependency_formats[0].1
+    } else {
+        let fmts = info
+            .dependency_formats
+            .iter()
+            .find_map(|&(ty, ref list)| if Some(ty) == crate_type { Some(list) } else { None });
+
+        let Some(fmts) = fmts else {
+            return Err(errors::LinkRlibError::MissingFormat);
+        };
+
+        fmts
     };
+
     for &cnum in crates {
         match fmts.get(cnum.as_usize() - 1) {
             Some(&Linkage::NotLinked | &Linkage::Dynamic | &Linkage::IncludedFromDylib) => continue,
@@ -449,7 +445,7 @@ fn link_rlib<'a>(
 /// Extract all symbols defined in raw-dylib libraries, collated by library name.
 ///
 /// If we have multiple extern blocks that specify symbols defined in the same raw-dylib library,
-/// then the CodegenResults value contains one NativeLib instance for each block.  However, the
+/// then the CodegenResults value contains one NativeLib instance for each block. However, the
 /// linker appears to expect only a single import library for each library used, so we need to
 /// collate the symbols together by library name before generating the import libraries.
 fn collate_raw_dylibs<'a, 'b>(
@@ -516,64 +512,71 @@ fn link_staticlib<'a>(
     )?;
     let mut all_native_libs = vec![];
 
-    let res = each_linked_rlib(sess, &codegen_results.crate_info, &mut |cnum, path| {
-        let name = codegen_results.crate_info.crate_name[&cnum];
-        let native_libs = &codegen_results.crate_info.native_libraries[&cnum];
-
-        // Here when we include the rlib into our staticlib we need to make a
-        // decision whether to include the extra object files along the way.
-        // These extra object files come from statically included native
-        // libraries, but they may be cfg'd away with #[link(cfg(..))].
-        //
-        // This unstable feature, though, only needs liblibc to work. The only
-        // use case there is where musl is statically included in liblibc.rlib,
-        // so if we don't want the included version we just need to skip it. As
-        // a result the logic here is that if *any* linked library is cfg'd away
-        // we just skip all object files.
-        //
-        // Clearly this is not sufficient for a general purpose feature, and
-        // we'd want to read from the library's metadata to determine which
-        // object files come from where and selectively skip them.
-        let skip_object_files = native_libs.iter().any(|lib| {
-            matches!(lib.kind, NativeLibKind::Static { bundle: None | Some(true), .. })
-                && !relevant_lib(sess, lib)
-        });
+    let res = each_linked_rlib(
+        &codegen_results.crate_info,
+        Some(CrateType::Staticlib),
+        &mut |cnum, path| {
+            let name = codegen_results.crate_info.crate_name[&cnum];
+            let native_libs = &codegen_results.crate_info.native_libraries[&cnum];
+
+            // Here when we include the rlib into our staticlib we need to make a
+            // decision whether to include the extra object files along the way.
+            // These extra object files come from statically included native
+            // libraries, but they may be cfg'd away with #[link(cfg(..))].
+            //
+            // This unstable feature, though, only needs liblibc to work. The only
+            // use case there is where musl is statically included in liblibc.rlib,
+            // so if we don't want the included version we just need to skip it. As
+            // a result the logic here is that if *any* linked library is cfg'd away
+            // we just skip all object files.
+            //
+            // Clearly this is not sufficient for a general purpose feature, and
+            // we'd want to read from the library's metadata to determine which
+            // object files come from where and selectively skip them.
+            let skip_object_files = native_libs.iter().any(|lib| {
+                matches!(lib.kind, NativeLibKind::Static { bundle: None | Some(true), .. })
+                    && !relevant_lib(sess, lib)
+            });
 
-        let lto = are_upstream_rust_objects_already_included(sess)
-            && !ignored_for_lto(sess, &codegen_results.crate_info, cnum);
+            let lto = are_upstream_rust_objects_already_included(sess)
+                && !ignored_for_lto(sess, &codegen_results.crate_info, cnum);
 
-        // Ignoring obj file starting with the crate name
-        // as simple comparison is not enough - there
-        // might be also an extra name suffix
-        let obj_start = name.as_str().to_owned();
+            // Ignoring obj file starting with the crate name
+            // as simple comparison is not enough - there
+            // might be also an extra name suffix
+            let obj_start = name.as_str().to_owned();
 
-        ab.add_archive(
-            path,
-            Box::new(move |fname: &str| {
-                // Ignore metadata files, no matter the name.
-                if fname == METADATA_FILENAME {
-                    return true;
-                }
+            ab.add_archive(
+                path,
+                Box::new(move |fname: &str| {
+                    // Ignore metadata files, no matter the name.
+                    if fname == METADATA_FILENAME {
+                        return true;
+                    }
 
-                // Don't include Rust objects if LTO is enabled
-                if lto && looks_like_rust_object_file(fname) {
-                    return true;
-                }
+                    // Don't include Rust objects if LTO is enabled
+                    if lto && looks_like_rust_object_file(fname) {
+                        return true;
+                    }
 
-                // Otherwise if this is *not* a rust object and we're skipping
-                // objects then skip this file
-                if skip_object_files && (!fname.starts_with(&obj_start) || !fname.ends_with(".o")) {
-                    return true;
-                }
+                    // Otherwise if this is *not* a rust object and we're skipping
+                    // objects then skip this file
+                    if skip_object_files
+                        && (!fname.starts_with(&obj_start) || !fname.ends_with(".o"))
+                    {
+                        return true;
+                    }
 
-                // ok, don't skip this
-                false
-            }),
-        )
-        .unwrap();
+                    // ok, don't skip this
+                    false
+                }),
+            )
+            .unwrap();
 
-        all_native_libs.extend(codegen_results.crate_info.native_libraries[&cnum].iter().cloned());
-    });
+            all_native_libs
+                .extend(codegen_results.crate_info.native_libraries[&cnum].iter().cloned());
+        },
+    );
     if let Err(e) = res {
         sess.emit_fatal(e);
     }
@@ -607,21 +610,21 @@ fn link_dwarf_object<'a>(
     }
 
     impl<Relocations> ThorinSession<Relocations> {
-        fn alloc_mmap<'arena>(&'arena self, data: Mmap) -> &'arena Mmap {
+        fn alloc_mmap(&self, data: Mmap) -> &Mmap {
             (*self.arena_mmap.alloc(data)).borrow()
         }
     }
 
     impl<Relocations> thorin::Session<Relocations> for ThorinSession<Relocations> {
-        fn alloc_data<'arena>(&'arena self, data: Vec<u8>) -> &'arena [u8] {
+        fn alloc_data(&self, data: Vec<u8>) -> &[u8] {
             (*self.arena_data.alloc(data)).borrow()
         }
 
-        fn alloc_relocation<'arena>(&'arena self, data: Relocations) -> &'arena Relocations {
+        fn alloc_relocation(&self, data: Relocations) -> &Relocations {
             (*self.arena_relocations.alloc(data)).borrow()
         }
 
-        fn read_input<'arena>(&'arena self, path: &Path) -> std::io::Result<&'arena [u8]> {
+        fn read_input(&self, path: &Path) -> std::io::Result<&[u8]> {
             let file = File::open(&path)?;
             let mmap = (unsafe { Mmap::map(file) })?;
             Ok(self.alloc_mmap(mmap))
@@ -722,7 +725,7 @@ fn link_natively<'a>(
 
     linker::disable_localization(&mut cmd);
 
-    for &(ref k, ref v) in sess.target.link_env.as_ref() {
+    for (k, v) in sess.target.link_env.as_ref() {
         cmd.env(k.as_ref(), v.as_ref());
     }
     for k in sess.target.link_env_remove.as_ref() {
@@ -1194,7 +1197,7 @@ pub fn linker_and_flavor(sess: &Session) -> (PathBuf, LinkerFlavor) {
                         if cfg!(any(target_os = "solaris", target_os = "illumos")) {
                             // On historical Solaris systems, "cc" may have
                             // been Sun Studio, which is not flag-compatible
-                            // with "gcc".  This history casts a long shadow,
+                            // with "gcc". This history casts a long shadow,
                             // and many modern illumos distributions today
                             // ship GCC as "gcc" without also making it
                             // available as "cc".
@@ -1228,12 +1231,23 @@ pub fn linker_and_flavor(sess: &Session) -> (PathBuf, LinkerFlavor) {
                     sess.emit_fatal(errors::LinkerFileStem);
                 });
 
+                // Remove any version postfix.
+                let stem = stem
+                    .rsplit_once('-')
+                    .and_then(|(lhs, rhs)| rhs.chars().all(char::is_numeric).then_some(lhs))
+                    .unwrap_or(stem);
+
+                // GCC/Clang can have an optional target prefix.
                 let flavor = if stem == "emcc" {
                     LinkerFlavor::EmCc
                 } else if stem == "gcc"
                     || stem.ends_with("-gcc")
+                    || stem == "g++"
+                    || stem.ends_with("-g++")
                     || stem == "clang"
                     || stem.ends_with("-clang")
+                    || stem == "clang++"
+                    || stem.ends_with("-clang++")
                 {
                     LinkerFlavor::from_cli(LinkerFlavorCli::Gcc, &sess.target)
                 } else if stem == "wasm-ld" || stem.ends_with("-wasm-ld") {
@@ -1354,7 +1368,8 @@ fn print_native_static_libs(sess: &Session, all_native_libs: &[NativeLib]) {
     if !lib_args.is_empty() {
         sess.emit_note(errors::StaticLibraryNativeArtifacts);
         // Prefix for greppability
-        sess.emit_note(errors::NativeStaticLibs { arguments: lib_args.join(" ") });
+        // Note: This must not be translated as tools are allowed to depend on this exact string.
+        sess.note_without_error(&format!("native-static-libs: {}", &lib_args.join(" ")));
     }
 }
 
@@ -2612,7 +2627,7 @@ fn add_static_crate<'a>(
             sess.target.no_builtins || !codegen_results.crate_info.is_no_builtins.contains(&cnum);
 
         let mut archive = archive_builder_builder.new_archive_builder(sess);
-        if let Err(e) = archive.add_archive(
+        if let Err(error) = archive.add_archive(
             cratepath,
             Box::new(move |f| {
                 if f == METADATA_FILENAME {
@@ -2652,7 +2667,7 @@ fn add_static_crate<'a>(
                 false
             }),
         ) {
-            sess.fatal(&format!("failed to build archive from rlib: {}", e));
+            sess.emit_fatal(errors::RlibArchiveBuildFailure { error });
         }
         if archive.build(&dst) {
             link_upstream(&dst);
@@ -2822,11 +2837,30 @@ fn add_gcc_ld_path(cmd: &mut dyn Linker, sess: &Session, flavor: LinkerFlavor) {
                     // Implement the "linker flavor" part of -Zgcc-ld
                     // by asking cc to use some kind of lld.
                     cmd.arg("-fuse-ld=lld");
+
                     if !flavor.is_gnu() {
                         // Tell clang to use a non-default LLD flavor.
                         // Gcc doesn't understand the target option, but we currently assume
                         // that gcc is not used for Apple and Wasm targets (#97402).
-                        cmd.arg(format!("--target={}", sess.target.llvm_target));
+                        //
+                        // Note that we don't want to do that by default on macOS: e.g. passing a
+                        // 10.7 target to LLVM works, but not to recent versions of clang/macOS, as
+                        // shown in issue #101653 and the discussion in PR #101792.
+                        //
+                        // It could be required in some cases of cross-compiling with
+                        // `-Zgcc-ld=lld`, but this is generally unspecified, and we don't know
+                        // which specific versions of clang, macOS SDK, host and target OS
+                        // combinations impact us here.
+                        //
+                        // So we do a simple first-approximation until we know more of what the
+                        // Apple targets require (and which would be handled prior to hitting this
+                        // `-Zgcc-ld=lld` codepath anyway), but the expectation is that until then
+                        // this should be manually passed if needed. We specify the target when
+                        // targeting a different linker flavor on macOS, and that's also always
+                        // the case when targeting WASM.
+                        if sess.target.linker_flavor != sess.host.linker_flavor {
+                            cmd.arg(format!("--target={}", sess.target.llvm_target));
+                        }
                     }
                 }
             }
diff --git a/compiler/rustc_codegen_ssa/src/back/linker.rs b/compiler/rustc_codegen_ssa/src/back/linker.rs
index f087d903e..eaf1e9817 100644
--- a/compiler/rustc_codegen_ssa/src/back/linker.rs
+++ b/compiler/rustc_codegen_ssa/src/back/linker.rs
@@ -108,7 +108,7 @@ pub fn get_linker<'a>(
     if sess.target.is_like_msvc {
         if let Some(ref tool) = msvc_tool {
             cmd.args(tool.args());
-            for &(ref k, ref v) in tool.env() {
+            for (k, v) in tool.env() {
                 if k == "PATH" {
                     new_path.extend(env::split_paths(v));
                     msvc_changed_path = true;
@@ -544,7 +544,7 @@ impl<'a> Linker for GccLinker<'a> {
         // link times negatively.
         //
         // -dead_strip can't be part of the pre_link_args because it's also used
-        // for partial linking when using multiple codegen units (-r).  So we
+        // for partial linking when using multiple codegen units (-r). So we
         // insert it here.
         if self.sess.target.is_like_osx {
             self.linker_arg("-dead_strip");
diff --git a/compiler/rustc_codegen_ssa/src/back/metadata.rs b/compiler/rustc_codegen_ssa/src/back/metadata.rs
index 51c5c375d..7d3c14fec 100644
--- a/compiler/rustc_codegen_ssa/src/back/metadata.rs
+++ b/compiler/rustc_codegen_ssa/src/back/metadata.rs
@@ -100,7 +100,13 @@ pub(crate) fn create_object_file(sess: &Session) -> Option<write::Object<'static
     };
     let architecture = match &sess.target.arch[..] {
         "arm" => Architecture::Arm,
-        "aarch64" => Architecture::Aarch64,
+        "aarch64" => {
+            if sess.target.pointer_width == 32 {
+                Architecture::Aarch64_Ilp32
+            } else {
+                Architecture::Aarch64
+            }
+        }
         "x86" => Architecture::I386,
         "s390x" => Architecture::S390x,
         "mips" => Architecture::Mips,
@@ -165,11 +171,23 @@ pub(crate) fn create_object_file(sess: &Session) -> Option<write::Object<'static
                 };
             e_flags
         }
-        Architecture::Riscv64 if sess.target.options.features.contains("+d") => {
-            // copied from `riscv64-linux-gnu-gcc foo.c -c`, note though
-            // that the `+d` target feature represents whether the double
-            // float abi is enabled.
-            let e_flags = elf::EF_RISCV_RVC | elf::EF_RISCV_FLOAT_ABI_DOUBLE;
+        Architecture::Riscv32 | Architecture::Riscv64 => {
+            // Source: https://github.com/riscv-non-isa/riscv-elf-psabi-doc/blob/079772828bd10933d34121117a222b4cc0ee2200/riscv-elf.adoc
+            let mut e_flags: u32 = 0x0;
+            let features = &sess.target.options.features;
+            // Check if compressed is enabled
+            if features.contains("+c") {
+                e_flags |= elf::EF_RISCV_RVC;
+            }
+
+            // Select the appropriate floating-point ABI
+            if features.contains("+d") {
+                e_flags |= elf::EF_RISCV_FLOAT_ABI_DOUBLE;
+            } else if features.contains("+f") {
+                e_flags |= elf::EF_RISCV_FLOAT_ABI_SINGLE;
+            } else {
+                e_flags |= elf::EF_RISCV_FLOAT_ABI_SOFT;
+            }
             e_flags
         }
         _ => 0,
diff --git a/compiler/rustc_codegen_ssa/src/back/symbol_export.rs b/compiler/rustc_codegen_ssa/src/back/symbol_export.rs
index 22f534d90..57a99e74c 100644
--- a/compiler/rustc_codegen_ssa/src/back/symbol_export.rs
+++ b/compiler/rustc_codegen_ssa/src/back/symbol_export.rs
@@ -163,21 +163,25 @@ fn is_reachable_non_generic_provider_extern(tcx: TyCtxt<'_>, def_id: DefId) -> b
     tcx.reachable_non_generics(def_id.krate).contains_key(&def_id)
 }
 
-fn exported_symbols_provider_local<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn exported_symbols_provider_local(
+    tcx: TyCtxt<'_>,
     cnum: CrateNum,
-) -> &'tcx [(ExportedSymbol<'tcx>, SymbolExportInfo)] {
+) -> &[(ExportedSymbol<'_>, SymbolExportInfo)] {
     assert_eq!(cnum, LOCAL_CRATE);
 
     if !tcx.sess.opts.output_types.should_codegen() {
         return &[];
     }
 
-    let mut symbols: Vec<_> = tcx
-        .reachable_non_generics(LOCAL_CRATE)
-        .iter()
-        .map(|(&def_id, &info)| (ExportedSymbol::NonGeneric(def_id), info))
-        .collect();
+    // FIXME: Sorting this is unnecessary since we are sorting later anyway.
+    //        Can we skip the later sorting?
+    let mut symbols: Vec<_> = tcx.with_stable_hashing_context(|hcx| {
+        tcx.reachable_non_generics(LOCAL_CRATE)
+            .to_sorted(&hcx, true)
+            .into_iter()
+            .map(|(&def_id, &info)| (ExportedSymbol::NonGeneric(def_id), info))
+            .collect()
+    });
 
     if tcx.entry_fn(()).is_some() {
         let exported_symbol =
diff --git a/compiler/rustc_codegen_ssa/src/back/write.rs b/compiler/rustc_codegen_ssa/src/back/write.rs
index 12fca6496..9f1614af7 100644
--- a/compiler/rustc_codegen_ssa/src/back/write.rs
+++ b/compiler/rustc_codegen_ssa/src/back/write.rs
@@ -105,7 +105,7 @@ pub struct ModuleConfig {
     pub emit_thin_lto: bool,
     pub bc_cmdline: String,
 
-    // Miscellaneous flags.  These are mostly copied from command-line
+    // Miscellaneous flags. These are mostly copied from command-line
     // options.
     pub verify_llvm_ir: bool,
     pub no_prepopulate_passes: bool,
@@ -538,7 +538,7 @@ fn produce_final_output_artifacts(
 
     let copy_if_one_unit = |output_type: OutputType, keep_numbered: bool| {
         if compiled_modules.modules.len() == 1 {
-            // 1) Only one codegen unit.  In this case it's no difficulty
+            // 1) Only one codegen unit. In this case it's no difficulty
             //    to copy `foo.0.x` to `foo.x`.
             let module_name = Some(&compiled_modules.modules[0].name[..]);
             let path = crate_output.temp_path(output_type, module_name);
@@ -557,15 +557,15 @@ fn produce_final_output_artifacts(
                 .to_owned();
 
             if crate_output.outputs.contains_key(&output_type) {
-                // 2) Multiple codegen units, with `--emit foo=some_name`.  We have
+                // 2) Multiple codegen units, with `--emit foo=some_name`. We have
                 //    no good solution for this case, so warn the user.
                 sess.emit_warning(errors::IgnoringEmitPath { extension });
             } else if crate_output.single_output_file.is_some() {
-                // 3) Multiple codegen units, with `-o some_name`.  We have
+                // 3) Multiple codegen units, with `-o some_name`. We have
                 //    no good solution for this case, so warn the user.
                 sess.emit_warning(errors::IgnoringOutput { extension });
             } else {
-                // 4) Multiple codegen units, but no explicit name.  We
+                // 4) Multiple codegen units, but no explicit name. We
                 //    just leave the `foo.0.x` files in place.
                 // (We don't have to do any work in this case.)
             }
@@ -579,7 +579,7 @@ fn produce_final_output_artifacts(
         match *output_type {
             OutputType::Bitcode => {
                 user_wants_bitcode = true;
-                // Copy to .bc, but always keep the .0.bc.  There is a later
+                // Copy to .bc, but always keep the .0.bc. There is a later
                 // check to figure out if we should delete .0.bc files, or keep
                 // them for making an rlib.
                 copy_if_one_unit(OutputType::Bitcode, true);
@@ -611,7 +611,7 @@ fn produce_final_output_artifacts(
     // `-C save-temps` or `--emit=` flags).
 
     if !sess.opts.cg.save_temps {
-        // Remove the temporary .#module-name#.o objects.  If the user didn't
+        // Remove the temporary .#module-name#.o objects. If the user didn't
         // explicitly request bitcode (with --emit=bc), and the bitcode is not
         // needed for building an rlib, then we must remove .#module-name#.bc as
         // well.
@@ -1002,7 +1002,7 @@ fn start_executing_work<B: ExtraBackendMethods>(
     let sess = tcx.sess;
 
     let mut each_linked_rlib_for_lto = Vec::new();
-    drop(link::each_linked_rlib(sess, crate_info, &mut |cnum, path| {
+    drop(link::each_linked_rlib(crate_info, None, &mut |cnum, path| {
         if link::ignored_for_lto(sess, crate_info, cnum) {
             return;
         }
@@ -1098,7 +1098,7 @@ fn start_executing_work<B: ExtraBackendMethods>(
     // There are a few environmental pre-conditions that shape how the system
     // is set up:
     //
-    // - Error reporting only can happen on the main thread because that's the
+    // - Error reporting can only happen on the main thread because that's the
     //   only place where we have access to the compiler `Session`.
     // - LLVM work can be done on any thread.
     // - Codegen can only happen on the main thread.
@@ -1110,16 +1110,16 @@ fn start_executing_work<B: ExtraBackendMethods>(
     // Error Reporting
     // ===============
     // The error reporting restriction is handled separately from the rest: We
-    // set up a `SharedEmitter` the holds an open channel to the main thread.
+    // set up a `SharedEmitter` that holds an open channel to the main thread.
     // When an error occurs on any thread, the shared emitter will send the
     // error message to the receiver main thread (`SharedEmitterMain`). The
     // main thread will periodically query this error message queue and emit
     // any error messages it has received. It might even abort compilation if
-    // has received a fatal error. In this case we rely on all other threads
+    // it has received a fatal error. In this case we rely on all other threads
     // being torn down automatically with the main thread.
     // Since the main thread will often be busy doing codegen work, error
     // reporting will be somewhat delayed, since the message queue can only be
-    // checked in between to work packages.
+    // checked in between two work packages.
     //
     // Work Processing Infrastructure
     // ==============================
@@ -1133,7 +1133,7 @@ fn start_executing_work<B: ExtraBackendMethods>(
     // thread about what work to do when, and it will spawn off LLVM worker
     // threads as open LLVM WorkItems become available.
     //
-    // The job of the main thread is to codegen CGUs into LLVM work package
+    // The job of the main thread is to codegen CGUs into LLVM work packages
     // (since the main thread is the only thread that can do this). The main
     // thread will block until it receives a message from the coordinator, upon
     // which it will codegen one CGU, send it to the coordinator and block
@@ -1142,10 +1142,10 @@ fn start_executing_work<B: ExtraBackendMethods>(
     //
     // The coordinator keeps a queue of LLVM WorkItems, and when a `Token` is
     // available, it will spawn off a new LLVM worker thread and let it process
-    // that a WorkItem. When a LLVM worker thread is done with its WorkItem,
+    // a WorkItem. When a LLVM worker thread is done with its WorkItem,
     // it will just shut down, which also frees all resources associated with
     // the given LLVM module, and sends a message to the coordinator that the
-    // has been completed.
+    // WorkItem has been completed.
     //
     // Work Scheduling
     // ===============
@@ -1165,7 +1165,7 @@ fn start_executing_work<B: ExtraBackendMethods>(
     //
     // Doing LLVM Work on the Main Thread
     // ----------------------------------
-    // Since the main thread owns the compiler processes implicit `Token`, it is
+    // Since the main thread owns the compiler process's implicit `Token`, it is
     // wasteful to keep it blocked without doing any work. Therefore, what we do
     // in this case is: We spawn off an additional LLVM worker thread that helps
     // reduce the queue. The work it is doing corresponds to the implicit
@@ -1216,7 +1216,7 @@ fn start_executing_work<B: ExtraBackendMethods>(
     // ------------------------------
     //
     // The final job the coordinator thread is responsible for is managing LTO
-    // and how that works. When LTO is requested what we'll to is collect all
+    // and how that works. When LTO is requested what we'll do is collect all
     // optimized LLVM modules into a local vector on the coordinator. Once all
     // modules have been codegened and optimized we hand this to the `lto`
     // module for further optimization. The `lto` module will return back a list
@@ -1899,7 +1899,7 @@ impl<B: ExtraBackendMethods> OngoingCodegen<B> {
 
         // FIXME: time_llvm_passes support - does this use a global context or
         // something?
-        if sess.codegen_units() == 1 && sess.time_llvm_passes() {
+        if sess.codegen_units() == 1 && sess.opts.unstable_opts.time_llvm_passes {
             self.backend.print_pass_timings()
         }
 
diff --git a/compiler/rustc_codegen_ssa/src/base.rs b/compiler/rustc_codegen_ssa/src/base.rs
index 4f396e970..32d3cfe6f 100644
--- a/compiler/rustc_codegen_ssa/src/base.rs
+++ b/compiler/rustc_codegen_ssa/src/base.rs
@@ -5,6 +5,7 @@ use crate::back::write::{
     submit_post_lto_module_to_llvm, submit_pre_lto_module_to_llvm, ComputedLtoType, OngoingCodegen,
 };
 use crate::common::{IntPredicate, RealPredicate, TypeKind};
+use crate::errors;
 use crate::meth;
 use crate::mir;
 use crate::mir::operand::OperandValue;
@@ -41,7 +42,6 @@ use rustc_span::{DebuggerVisualizerFile, DebuggerVisualizerType};
 use rustc_target::abi::{Align, Size, VariantIdx};
 
 use std::collections::BTreeSet;
-use std::convert::TryFrom;
 use std::time::{Duration, Instant};
 
 use itertools::Itertools;
@@ -153,9 +153,7 @@ pub fn unsized_info<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
         (
             &ty::Dynamic(ref data_a, _, src_dyn_kind),
             &ty::Dynamic(ref data_b, _, target_dyn_kind),
-        ) => {
-            assert_eq!(src_dyn_kind, target_dyn_kind);
-
+        ) if src_dyn_kind == target_dyn_kind => {
             let old_info =
                 old_info.expect("unsized_info: missing old info for trait upcasting coercion");
             if data_a.principal_def_id() == data_b.principal_def_id() {
@@ -452,10 +450,7 @@ pub fn maybe_create_entry_wrapper<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
         let Some(llfn) = cx.declare_c_main(llfty) else {
             // FIXME: We should be smart and show a better diagnostic here.
             let span = cx.tcx().def_span(rust_main_def_id);
-            cx.sess()
-                .struct_span_err(span, "entry symbol `main` declared multiple times")
-                .help("did you use `#[no_mangle]` on `fn main`? Use `#[start]` instead")
-                .emit();
+            cx.sess().emit_err(errors::MultipleMainFunctions { span });
             cx.sess().abort_if_errors();
             bug!();
         };
@@ -596,8 +591,8 @@ pub fn codegen_crate<B: ExtraBackendMethods>(
                 &metadata,
                 &exported_symbols::metadata_symbol_name(tcx),
             );
-            if let Err(err) = std::fs::write(&file_name, data) {
-                tcx.sess.fatal(&format!("error writing metadata object file: {}", err));
+            if let Err(error) = std::fs::write(&file_name, data) {
+                tcx.sess.emit_fatal(errors::MetadataObjectFileWrite { error });
             }
             Some(CompiledModule {
                 name: metadata_cgu_name,
@@ -682,7 +677,7 @@ pub fn codegen_crate<B: ExtraBackendMethods>(
     });
 
     let mut total_codegen_time = Duration::new(0, 0);
-    let start_rss = tcx.sess.time_passes().then(|| get_resident_set_size());
+    let start_rss = tcx.sess.opts.unstable_opts.time_passes.then(|| get_resident_set_size());
 
     // The non-parallel compiler can only translate codegen units to LLVM IR
     // on a single thread, leading to a staircase effect where the N LLVM
@@ -782,7 +777,7 @@ pub fn codegen_crate<B: ExtraBackendMethods>(
 
     // Since the main thread is sometimes blocked during codegen, we keep track
     // -Ztime-passes output manually.
-    if tcx.sess.time_passes() {
+    if tcx.sess.opts.unstable_opts.time_passes {
         let end_rss = get_resident_set_size();
 
         print_time_passes_entry(
@@ -816,11 +811,7 @@ impl CrateInfo {
         let subsystem = tcx.sess.first_attr_value_str_by_name(crate_attrs, sym::windows_subsystem);
         let windows_subsystem = subsystem.map(|subsystem| {
             if subsystem != sym::windows && subsystem != sym::console {
-                tcx.sess.fatal(&format!(
-                    "invalid windows subsystem `{}`, only \
-                                     `windows` and `console` are allowed",
-                    subsystem
-                ));
+                tcx.sess.emit_fatal(errors::InvalidWindowsSubsystem { subsystem });
             }
             subsystem.to_string()
         });
@@ -973,16 +964,19 @@ pub fn provide(providers: &mut Providers) {
         };
 
         let (defids, _) = tcx.collect_and_partition_mono_items(cratenum);
-        for id in &*defids {
+
+        let any_for_speed = defids.items().any(|id| {
             let CodegenFnAttrs { optimize, .. } = tcx.codegen_fn_attrs(*id);
             match optimize {
-                attr::OptimizeAttr::None => continue,
-                attr::OptimizeAttr::Size => continue,
-                attr::OptimizeAttr::Speed => {
-                    return for_speed;
-                }
+                attr::OptimizeAttr::None | attr::OptimizeAttr::Size => false,
+                attr::OptimizeAttr::Speed => true,
             }
+        });
+
+        if any_for_speed {
+            return for_speed;
         }
+
         tcx.sess.opts.optimize
     };
 }
diff --git a/compiler/rustc_codegen_ssa/src/codegen_attrs.rs b/compiler/rustc_codegen_ssa/src/codegen_attrs.rs
new file mode 100644
index 000000000..8808ad2dc
--- /dev/null
+++ b/compiler/rustc_codegen_ssa/src/codegen_attrs.rs
@@ -0,0 +1,709 @@
+use rustc_ast::{ast, MetaItemKind, NestedMetaItem};
+use rustc_attr::{list_contains_name, InlineAttr, InstructionSetAttr, OptimizeAttr};
+use rustc_errors::struct_span_err;
+use rustc_hir as hir;
+use rustc_hir::def::DefKind;
+use rustc_hir::def_id::{DefId, LocalDefId, LOCAL_CRATE};
+use rustc_hir::{lang_items, weak_lang_items::WEAK_LANG_ITEMS, LangItem};
+use rustc_middle::middle::codegen_fn_attrs::{CodegenFnAttrFlags, CodegenFnAttrs};
+use rustc_middle::mir::mono::Linkage;
+use rustc_middle::ty::query::Providers;
+use rustc_middle::ty::{self as ty, DefIdTree, TyCtxt};
+use rustc_session::{lint, parse::feature_err};
+use rustc_span::{sym, Span};
+use rustc_target::spec::{abi, SanitizerSet};
+
+use crate::target_features::from_target_feature;
+use crate::{errors::ExpectedUsedSymbol, target_features::check_target_feature_trait_unsafe};
+
+fn linkage_by_name(tcx: TyCtxt<'_>, def_id: LocalDefId, name: &str) -> Linkage {
+    use rustc_middle::mir::mono::Linkage::*;
+
+    // Use the names from src/llvm/docs/LangRef.rst here. Most types are only
+    // applicable to variable declarations and may not really make sense for
+    // Rust code in the first place but allow them anyway and trust that the
+    // user knows what they're doing. Who knows, unanticipated use cases may pop
+    // up in the future.
+    //
+    // ghost, dllimport, dllexport and linkonce_odr_autohide are not supported
+    // and don't have to be, LLVM treats them as no-ops.
+    match name {
+        "appending" => Appending,
+        "available_externally" => AvailableExternally,
+        "common" => Common,
+        "extern_weak" => ExternalWeak,
+        "external" => External,
+        "internal" => Internal,
+        "linkonce" => LinkOnceAny,
+        "linkonce_odr" => LinkOnceODR,
+        "private" => Private,
+        "weak" => WeakAny,
+        "weak_odr" => WeakODR,
+        _ => tcx.sess.span_fatal(tcx.def_span(def_id), "invalid linkage specified"),
+    }
+}
+
+fn codegen_fn_attrs(tcx: TyCtxt<'_>, did: DefId) -> CodegenFnAttrs {
+    if cfg!(debug_assertions) {
+        let def_kind = tcx.def_kind(did);
+        assert!(
+            def_kind.has_codegen_attrs(),
+            "unexpected `def_kind` in `codegen_fn_attrs`: {def_kind:?}",
+        );
+    }
+
+    let did = did.expect_local();
+    let attrs = tcx.hir().attrs(tcx.hir().local_def_id_to_hir_id(did));
+    let mut codegen_fn_attrs = CodegenFnAttrs::new();
+    if tcx.should_inherit_track_caller(did) {
+        codegen_fn_attrs.flags |= CodegenFnAttrFlags::TRACK_CALLER;
+    }
+
+    let supported_target_features = tcx.supported_target_features(LOCAL_CRATE);
+
+    // In some cases, attribute are only valid on functions, but it's the `check_attr`
+    // pass that check that they aren't used anywhere else, rather this module.
+    // In these cases, we bail from performing further checks that are only meaningful for
+    // functions (such as calling `fn_sig`, which ICEs if given a non-function). We also
+    // report a delayed bug, just in case `check_attr` isn't doing its job.
+    let validate_fn_only_attr = |attr_sp| -> bool {
+        let def_kind = tcx.def_kind(did);
+        if let DefKind::Fn | DefKind::AssocFn | DefKind::Variant | DefKind::Ctor(..) = def_kind {
+            true
+        } else {
+            tcx.sess.delay_span_bug(attr_sp, "this attribute can only be applied to functions");
+            false
+        }
+    };
+
+    let mut inline_span = None;
+    let mut link_ordinal_span = None;
+    let mut no_sanitize_span = None;
+    for attr in attrs.iter() {
+        if attr.has_name(sym::cold) {
+            codegen_fn_attrs.flags |= CodegenFnAttrFlags::COLD;
+        } else if attr.has_name(sym::rustc_allocator) {
+            codegen_fn_attrs.flags |= CodegenFnAttrFlags::ALLOCATOR;
+        } else if attr.has_name(sym::ffi_returns_twice) {
+            if tcx.is_foreign_item(did) {
+                codegen_fn_attrs.flags |= CodegenFnAttrFlags::FFI_RETURNS_TWICE;
+            } else {
+                // `#[ffi_returns_twice]` is only allowed `extern fn`s.
+                struct_span_err!(
+                    tcx.sess,
+                    attr.span,
+                    E0724,
+                    "`#[ffi_returns_twice]` may only be used on foreign functions"
+                )
+                .emit();
+            }
+        } else if attr.has_name(sym::ffi_pure) {
+            if tcx.is_foreign_item(did) {
+                if attrs.iter().any(|a| a.has_name(sym::ffi_const)) {
+                    // `#[ffi_const]` functions cannot be `#[ffi_pure]`
+                    struct_span_err!(
+                        tcx.sess,
+                        attr.span,
+                        E0757,
+                        "`#[ffi_const]` function cannot be `#[ffi_pure]`"
+                    )
+                    .emit();
+                } else {
+                    codegen_fn_attrs.flags |= CodegenFnAttrFlags::FFI_PURE;
+                }
+            } else {
+                // `#[ffi_pure]` is only allowed on foreign functions
+                struct_span_err!(
+                    tcx.sess,
+                    attr.span,
+                    E0755,
+                    "`#[ffi_pure]` may only be used on foreign functions"
+                )
+                .emit();
+            }
+        } else if attr.has_name(sym::ffi_const) {
+            if tcx.is_foreign_item(did) {
+                codegen_fn_attrs.flags |= CodegenFnAttrFlags::FFI_CONST;
+            } else {
+                // `#[ffi_const]` is only allowed on foreign functions
+                struct_span_err!(
+                    tcx.sess,
+                    attr.span,
+                    E0756,
+                    "`#[ffi_const]` may only be used on foreign functions"
+                )
+                .emit();
+            }
+        } else if attr.has_name(sym::rustc_nounwind) {
+            codegen_fn_attrs.flags |= CodegenFnAttrFlags::NEVER_UNWIND;
+        } else if attr.has_name(sym::rustc_reallocator) {
+            codegen_fn_attrs.flags |= CodegenFnAttrFlags::REALLOCATOR;
+        } else if attr.has_name(sym::rustc_deallocator) {
+            codegen_fn_attrs.flags |= CodegenFnAttrFlags::DEALLOCATOR;
+        } else if attr.has_name(sym::rustc_allocator_zeroed) {
+            codegen_fn_attrs.flags |= CodegenFnAttrFlags::ALLOCATOR_ZEROED;
+        } else if attr.has_name(sym::naked) {
+            codegen_fn_attrs.flags |= CodegenFnAttrFlags::NAKED;
+        } else if attr.has_name(sym::no_mangle) {
+            codegen_fn_attrs.flags |= CodegenFnAttrFlags::NO_MANGLE;
+        } else if attr.has_name(sym::no_coverage) {
+            codegen_fn_attrs.flags |= CodegenFnAttrFlags::NO_COVERAGE;
+        } else if attr.has_name(sym::rustc_std_internal_symbol) {
+            codegen_fn_attrs.flags |= CodegenFnAttrFlags::RUSTC_STD_INTERNAL_SYMBOL;
+        } else if attr.has_name(sym::used) {
+            let inner = attr.meta_item_list();
+            match inner.as_deref() {
+                Some([item]) if item.has_name(sym::linker) => {
+                    if !tcx.features().used_with_arg {
+                        feature_err(
+                            &tcx.sess.parse_sess,
+                            sym::used_with_arg,
+                            attr.span,
+                            "`#[used(linker)]` is currently unstable",
+                        )
+                        .emit();
+                    }
+                    codegen_fn_attrs.flags |= CodegenFnAttrFlags::USED_LINKER;
+                }
+                Some([item]) if item.has_name(sym::compiler) => {
+                    if !tcx.features().used_with_arg {
+                        feature_err(
+                            &tcx.sess.parse_sess,
+                            sym::used_with_arg,
+                            attr.span,
+                            "`#[used(compiler)]` is currently unstable",
+                        )
+                        .emit();
+                    }
+                    codegen_fn_attrs.flags |= CodegenFnAttrFlags::USED;
+                }
+                Some(_) => {
+                    tcx.sess.emit_err(ExpectedUsedSymbol { span: attr.span });
+                }
+                None => {
+                    // Unfortunately, unconditionally using `llvm.used` causes
+                    // issues in handling `.init_array` with the gold linker,
+                    // but using `llvm.compiler.used` caused a nontrival amount
+                    // of unintentional ecosystem breakage -- particularly on
+                    // Mach-O targets.
+                    //
+                    // As a result, we emit `llvm.compiler.used` only on ELF
+                    // targets. This is somewhat ad-hoc, but actually follows
+                    // our pre-LLVM 13 behavior (prior to the ecosystem
+                    // breakage), and seems to match `clang`'s behavior as well
+                    // (both before and after LLVM 13), possibly because they
+                    // have similar compatibility concerns to us. See
+                    // https://github.com/rust-lang/rust/issues/47384#issuecomment-1019080146
+                    // and following comments for some discussion of this, as
+                    // well as the comments in `rustc_codegen_llvm` where these
+                    // flags are handled.
+                    //
+                    // Anyway, to be clear: this is still up in the air
+                    // somewhat, and is subject to change in the future (which
+                    // is a good thing, because this would ideally be a bit
+                    // more firmed up).
+                    let is_like_elf = !(tcx.sess.target.is_like_osx
+                        || tcx.sess.target.is_like_windows
+                        || tcx.sess.target.is_like_wasm);
+                    codegen_fn_attrs.flags |= if is_like_elf {
+                        CodegenFnAttrFlags::USED
+                    } else {
+                        CodegenFnAttrFlags::USED_LINKER
+                    };
+                }
+            }
+        } else if attr.has_name(sym::cmse_nonsecure_entry) {
+            if validate_fn_only_attr(attr.span)
+                && !matches!(tcx.fn_sig(did).abi(), abi::Abi::C { .. })
+            {
+                struct_span_err!(
+                    tcx.sess,
+                    attr.span,
+                    E0776,
+                    "`#[cmse_nonsecure_entry]` requires C ABI"
+                )
+                .emit();
+            }
+            if !tcx.sess.target.llvm_target.contains("thumbv8m") {
+                struct_span_err!(tcx.sess, attr.span, E0775, "`#[cmse_nonsecure_entry]` is only valid for targets with the TrustZone-M extension")
+                    .emit();
+            }
+            codegen_fn_attrs.flags |= CodegenFnAttrFlags::CMSE_NONSECURE_ENTRY;
+        } else if attr.has_name(sym::thread_local) {
+            codegen_fn_attrs.flags |= CodegenFnAttrFlags::THREAD_LOCAL;
+        } else if attr.has_name(sym::track_caller) {
+            if !tcx.is_closure(did.to_def_id())
+                && validate_fn_only_attr(attr.span)
+                && tcx.fn_sig(did).abi() != abi::Abi::Rust
+            {
+                struct_span_err!(tcx.sess, attr.span, E0737, "`#[track_caller]` requires Rust ABI")
+                    .emit();
+            }
+            if tcx.is_closure(did.to_def_id()) && !tcx.features().closure_track_caller {
+                feature_err(
+                    &tcx.sess.parse_sess,
+                    sym::closure_track_caller,
+                    attr.span,
+                    "`#[track_caller]` on closures is currently unstable",
+                )
+                .emit();
+            }
+            codegen_fn_attrs.flags |= CodegenFnAttrFlags::TRACK_CALLER;
+        } else if attr.has_name(sym::export_name) {
+            if let Some(s) = attr.value_str() {
+                if s.as_str().contains('\0') {
+                    // `#[export_name = ...]` will be converted to a null-terminated string,
+                    // so it may not contain any null characters.
+                    struct_span_err!(
+                        tcx.sess,
+                        attr.span,
+                        E0648,
+                        "`export_name` may not contain null characters"
+                    )
+                    .emit();
+                }
+                codegen_fn_attrs.export_name = Some(s);
+            }
+        } else if attr.has_name(sym::target_feature) {
+            if !tcx.is_closure(did.to_def_id())
+                && tcx.fn_sig(did).unsafety() == hir::Unsafety::Normal
+            {
+                if tcx.sess.target.is_like_wasm || tcx.sess.opts.actually_rustdoc {
+                    // The `#[target_feature]` attribute is allowed on
+                    // WebAssembly targets on all functions, including safe
+                    // ones. Other targets require that `#[target_feature]` is
+                    // only applied to unsafe functions (pending the
+                    // `target_feature_11` feature) because on most targets
+                    // execution of instructions that are not supported is
+                    // considered undefined behavior. For WebAssembly which is a
+                    // 100% safe target at execution time it's not possible to
+                    // execute undefined instructions, and even if a future
+                    // feature was added in some form for this it would be a
+                    // deterministic trap. There is no undefined behavior when
+                    // executing WebAssembly so `#[target_feature]` is allowed
+                    // on safe functions (but again, only for WebAssembly)
+                    //
+                    // Note that this is also allowed if `actually_rustdoc` so
+                    // if a target is documenting some wasm-specific code then
+                    // it's not spuriously denied.
+                } else if !tcx.features().target_feature_11 {
+                    let mut err = feature_err(
+                        &tcx.sess.parse_sess,
+                        sym::target_feature_11,
+                        attr.span,
+                        "`#[target_feature(..)]` can only be applied to `unsafe` functions",
+                    );
+                    err.span_label(tcx.def_span(did), "not an `unsafe` function");
+                    err.emit();
+                } else {
+                    check_target_feature_trait_unsafe(tcx, did, attr.span);
+                }
+            }
+            from_target_feature(
+                tcx,
+                attr,
+                supported_target_features,
+                &mut codegen_fn_attrs.target_features,
+            );
+        } else if attr.has_name(sym::linkage) {
+            if let Some(val) = attr.value_str() {
+                let linkage = Some(linkage_by_name(tcx, did, val.as_str()));
+                if tcx.is_foreign_item(did) {
+                    codegen_fn_attrs.import_linkage = linkage;
+                } else {
+                    codegen_fn_attrs.linkage = linkage;
+                }
+            }
+        } else if attr.has_name(sym::link_section) {
+            if let Some(val) = attr.value_str() {
+                if val.as_str().bytes().any(|b| b == 0) {
+                    let msg = format!(
+                        "illegal null byte in link_section \
+                         value: `{}`",
+                        &val
+                    );
+                    tcx.sess.span_err(attr.span, &msg);
+                } else {
+                    codegen_fn_attrs.link_section = Some(val);
+                }
+            }
+        } else if attr.has_name(sym::link_name) {
+            codegen_fn_attrs.link_name = attr.value_str();
+        } else if attr.has_name(sym::link_ordinal) {
+            link_ordinal_span = Some(attr.span);
+            if let ordinal @ Some(_) = check_link_ordinal(tcx, attr) {
+                codegen_fn_attrs.link_ordinal = ordinal;
+            }
+        } else if attr.has_name(sym::no_sanitize) {
+            no_sanitize_span = Some(attr.span);
+            if let Some(list) = attr.meta_item_list() {
+                for item in list.iter() {
+                    if item.has_name(sym::address) {
+                        codegen_fn_attrs.no_sanitize |= SanitizerSet::ADDRESS;
+                    } else if item.has_name(sym::cfi) {
+                        codegen_fn_attrs.no_sanitize |= SanitizerSet::CFI;
+                    } else if item.has_name(sym::kcfi) {
+                        codegen_fn_attrs.no_sanitize |= SanitizerSet::KCFI;
+                    } else if item.has_name(sym::memory) {
+                        codegen_fn_attrs.no_sanitize |= SanitizerSet::MEMORY;
+                    } else if item.has_name(sym::memtag) {
+                        codegen_fn_attrs.no_sanitize |= SanitizerSet::MEMTAG;
+                    } else if item.has_name(sym::shadow_call_stack) {
+                        codegen_fn_attrs.no_sanitize |= SanitizerSet::SHADOWCALLSTACK;
+                    } else if item.has_name(sym::thread) {
+                        codegen_fn_attrs.no_sanitize |= SanitizerSet::THREAD;
+                    } else if item.has_name(sym::hwaddress) {
+                        codegen_fn_attrs.no_sanitize |= SanitizerSet::HWADDRESS;
+                    } else {
+                        tcx.sess
+                            .struct_span_err(item.span(), "invalid argument for `no_sanitize`")
+                            .note("expected one of: `address`, `cfi`, `hwaddress`, `kcfi`, `memory`, `memtag`, `shadow-call-stack`, or `thread`")
+                            .emit();
+                    }
+                }
+            }
+        } else if attr.has_name(sym::instruction_set) {
+            codegen_fn_attrs.instruction_set = match attr.meta_kind() {
+                Some(MetaItemKind::List(ref items)) => match items.as_slice() {
+                    [NestedMetaItem::MetaItem(set)] => {
+                        let segments =
+                            set.path.segments.iter().map(|x| x.ident.name).collect::<Vec<_>>();
+                        match segments.as_slice() {
+                            [sym::arm, sym::a32] | [sym::arm, sym::t32] => {
+                                if !tcx.sess.target.has_thumb_interworking {
+                                    struct_span_err!(
+                                        tcx.sess.diagnostic(),
+                                        attr.span,
+                                        E0779,
+                                        "target does not support `#[instruction_set]`"
+                                    )
+                                    .emit();
+                                    None
+                                } else if segments[1] == sym::a32 {
+                                    Some(InstructionSetAttr::ArmA32)
+                                } else if segments[1] == sym::t32 {
+                                    Some(InstructionSetAttr::ArmT32)
+                                } else {
+                                    unreachable!()
+                                }
+                            }
+                            _ => {
+                                struct_span_err!(
+                                    tcx.sess.diagnostic(),
+                                    attr.span,
+                                    E0779,
+                                    "invalid instruction set specified",
+                                )
+                                .emit();
+                                None
+                            }
+                        }
+                    }
+                    [] => {
+                        struct_span_err!(
+                            tcx.sess.diagnostic(),
+                            attr.span,
+                            E0778,
+                            "`#[instruction_set]` requires an argument"
+                        )
+                        .emit();
+                        None
+                    }
+                    _ => {
+                        struct_span_err!(
+                            tcx.sess.diagnostic(),
+                            attr.span,
+                            E0779,
+                            "cannot specify more than one instruction set"
+                        )
+                        .emit();
+                        None
+                    }
+                },
+                _ => {
+                    struct_span_err!(
+                        tcx.sess.diagnostic(),
+                        attr.span,
+                        E0778,
+                        "must specify an instruction set"
+                    )
+                    .emit();
+                    None
+                }
+            };
+        } else if attr.has_name(sym::repr) {
+            codegen_fn_attrs.alignment = match attr.meta_item_list() {
+                Some(items) => match items.as_slice() {
+                    [item] => match item.name_value_literal() {
+                        Some((sym::align, literal)) => {
+                            let alignment = rustc_attr::parse_alignment(&literal.kind);
+
+                            match alignment {
+                                Ok(align) => Some(align),
+                                Err(msg) => {
+                                    struct_span_err!(
+                                        tcx.sess.diagnostic(),
+                                        attr.span,
+                                        E0589,
+                                        "invalid `repr(align)` attribute: {}",
+                                        msg
+                                    )
+                                    .emit();
+
+                                    None
+                                }
+                            }
+                        }
+                        _ => None,
+                    },
+                    [] => None,
+                    _ => None,
+                },
+                None => None,
+            };
+        }
+    }
+
+    codegen_fn_attrs.inline = attrs.iter().fold(InlineAttr::None, |ia, attr| {
+        if !attr.has_name(sym::inline) {
+            return ia;
+        }
+        match attr.meta_kind() {
+            Some(MetaItemKind::Word) => InlineAttr::Hint,
+            Some(MetaItemKind::List(ref items)) => {
+                inline_span = Some(attr.span);
+                if items.len() != 1 {
+                    struct_span_err!(
+                        tcx.sess.diagnostic(),
+                        attr.span,
+                        E0534,
+                        "expected one argument"
+                    )
+                    .emit();
+                    InlineAttr::None
+                } else if list_contains_name(&items, sym::always) {
+                    InlineAttr::Always
+                } else if list_contains_name(&items, sym::never) {
+                    InlineAttr::Never
+                } else {
+                    struct_span_err!(
+                        tcx.sess.diagnostic(),
+                        items[0].span(),
+                        E0535,
+                        "invalid argument"
+                    )
+                    .help("valid inline arguments are `always` and `never`")
+                    .emit();
+
+                    InlineAttr::None
+                }
+            }
+            Some(MetaItemKind::NameValue(_)) => ia,
+            None => ia,
+        }
+    });
+
+    codegen_fn_attrs.optimize = attrs.iter().fold(OptimizeAttr::None, |ia, attr| {
+        if !attr.has_name(sym::optimize) {
+            return ia;
+        }
+        let err = |sp, s| struct_span_err!(tcx.sess.diagnostic(), sp, E0722, "{}", s).emit();
+        match attr.meta_kind() {
+            Some(MetaItemKind::Word) => {
+                err(attr.span, "expected one argument");
+                ia
+            }
+            Some(MetaItemKind::List(ref items)) => {
+                inline_span = Some(attr.span);
+                if items.len() != 1 {
+                    err(attr.span, "expected one argument");
+                    OptimizeAttr::None
+                } else if list_contains_name(&items, sym::size) {
+                    OptimizeAttr::Size
+                } else if list_contains_name(&items, sym::speed) {
+                    OptimizeAttr::Speed
+                } else {
+                    err(items[0].span(), "invalid argument");
+                    OptimizeAttr::None
+                }
+            }
+            Some(MetaItemKind::NameValue(_)) => ia,
+            None => ia,
+        }
+    });
+
+    // #73631: closures inherit `#[target_feature]` annotations
+    if tcx.features().target_feature_11 && tcx.is_closure(did.to_def_id()) {
+        let owner_id = tcx.parent(did.to_def_id());
+        if tcx.def_kind(owner_id).has_codegen_attrs() {
+            codegen_fn_attrs
+                .target_features
+                .extend(tcx.codegen_fn_attrs(owner_id).target_features.iter().copied());
+        }
+    }
+
+    // If a function uses #[target_feature] it can't be inlined into general
+    // purpose functions as they wouldn't have the right target features
+    // enabled. For that reason we also forbid #[inline(always)] as it can't be
+    // respected.
+    if !codegen_fn_attrs.target_features.is_empty() {
+        if codegen_fn_attrs.inline == InlineAttr::Always {
+            if let Some(span) = inline_span {
+                tcx.sess.span_err(
+                    span,
+                    "cannot use `#[inline(always)]` with \
+                     `#[target_feature]`",
+                );
+            }
+        }
+    }
+
+    if !codegen_fn_attrs.no_sanitize.is_empty() {
+        if codegen_fn_attrs.inline == InlineAttr::Always {
+            if let (Some(no_sanitize_span), Some(inline_span)) = (no_sanitize_span, inline_span) {
+                let hir_id = tcx.hir().local_def_id_to_hir_id(did);
+                tcx.struct_span_lint_hir(
+                    lint::builtin::INLINE_NO_SANITIZE,
+                    hir_id,
+                    no_sanitize_span,
+                    "`no_sanitize` will have no effect after inlining",
+                    |lint| lint.span_note(inline_span, "inlining requested here"),
+                )
+            }
+        }
+    }
+
+    if codegen_fn_attrs.flags.contains(CodegenFnAttrFlags::NAKED) {
+        codegen_fn_attrs.flags |= CodegenFnAttrFlags::NO_COVERAGE;
+        codegen_fn_attrs.inline = InlineAttr::Never;
+    }
+
+    // Weak lang items have the same semantics as "std internal" symbols in the
+    // sense that they're preserved through all our LTO passes and only
+    // strippable by the linker.
+    //
+    // Additionally weak lang items have predetermined symbol names.
+    if WEAK_LANG_ITEMS.iter().any(|&l| tcx.lang_items().get(l) == Some(did.to_def_id())) {
+        codegen_fn_attrs.flags |= CodegenFnAttrFlags::RUSTC_STD_INTERNAL_SYMBOL;
+    }
+    if let Some((name, _)) = lang_items::extract(attrs)
+        && let Some(lang_item) = LangItem::from_name(name)
+        && let Some(link_name) = lang_item.link_name()
+    {
+        codegen_fn_attrs.export_name = Some(link_name);
+        codegen_fn_attrs.link_name = Some(link_name);
+    }
+    check_link_name_xor_ordinal(tcx, &codegen_fn_attrs, link_ordinal_span);
+
+    // Internal symbols to the standard library all have no_mangle semantics in
+    // that they have defined symbol names present in the function name. This
+    // also applies to weak symbols where they all have known symbol names.
+    if codegen_fn_attrs.flags.contains(CodegenFnAttrFlags::RUSTC_STD_INTERNAL_SYMBOL) {
+        codegen_fn_attrs.flags |= CodegenFnAttrFlags::NO_MANGLE;
+    }
+
+    // Any linkage to LLVM intrinsics for now forcibly marks them all as never
+    // unwinds since LLVM sometimes can't handle codegen which `invoke`s
+    // intrinsic functions.
+    if let Some(name) = &codegen_fn_attrs.link_name {
+        if name.as_str().starts_with("llvm.") {
+            codegen_fn_attrs.flags |= CodegenFnAttrFlags::NEVER_UNWIND;
+        }
+    }
+
+    codegen_fn_attrs
+}
+
+/// Checks if the provided DefId is a method in a trait impl for a trait which has track_caller
+/// applied to the method prototype.
+fn should_inherit_track_caller(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
+    if let Some(impl_item) = tcx.opt_associated_item(def_id)
+        && let ty::AssocItemContainer::ImplContainer = impl_item.container
+        && let Some(trait_item) = impl_item.trait_item_def_id
+    {
+        return tcx
+            .codegen_fn_attrs(trait_item)
+            .flags
+            .intersects(CodegenFnAttrFlags::TRACK_CALLER);
+    }
+
+    false
+}
+
+fn check_link_ordinal(tcx: TyCtxt<'_>, attr: &ast::Attribute) -> Option<u16> {
+    use rustc_ast::{LitIntType, LitKind, MetaItemLit};
+    if !tcx.features().raw_dylib && tcx.sess.target.arch == "x86" {
+        feature_err(
+            &tcx.sess.parse_sess,
+            sym::raw_dylib,
+            attr.span,
+            "`#[link_ordinal]` is unstable on x86",
+        )
+        .emit();
+    }
+    let meta_item_list = attr.meta_item_list();
+    let meta_item_list = meta_item_list.as_deref();
+    let sole_meta_list = match meta_item_list {
+        Some([item]) => item.lit(),
+        Some(_) => {
+            tcx.sess
+                .struct_span_err(attr.span, "incorrect number of arguments to `#[link_ordinal]`")
+                .note("the attribute requires exactly one argument")
+                .emit();
+            return None;
+        }
+        _ => None,
+    };
+    if let Some(MetaItemLit { kind: LitKind::Int(ordinal, LitIntType::Unsuffixed), .. }) =
+        sole_meta_list
+    {
+        // According to the table at https://docs.microsoft.com/en-us/windows/win32/debug/pe-format#import-header,
+        // the ordinal must fit into 16 bits. Similarly, the Ordinal field in COFFShortExport (defined
+        // in llvm/include/llvm/Object/COFFImportFile.h), which we use to communicate import information
+        // to LLVM for `#[link(kind = "raw-dylib"_])`, is also defined to be uint16_t.
+        //
+        // FIXME: should we allow an ordinal of 0?  The MSVC toolchain has inconsistent support for this:
+        // both LINK.EXE and LIB.EXE signal errors and abort when given a .DEF file that specifies
+        // a zero ordinal. However, llvm-dlltool is perfectly happy to generate an import library
+        // for such a .DEF file, and MSVC's LINK.EXE is also perfectly happy to consume an import
+        // library produced by LLVM with an ordinal of 0, and it generates an .EXE.  (I don't know yet
+        // if the resulting EXE runs, as I haven't yet built the necessary DLL -- see earlier comment
+        // about LINK.EXE failing.)
+        if *ordinal <= u16::MAX as u128 {
+            Some(*ordinal as u16)
+        } else {
+            let msg = format!("ordinal value in `link_ordinal` is too large: `{}`", &ordinal);
+            tcx.sess
+                .struct_span_err(attr.span, &msg)
+                .note("the value may not exceed `u16::MAX`")
+                .emit();
+            None
+        }
+    } else {
+        tcx.sess
+            .struct_span_err(attr.span, "illegal ordinal format in `link_ordinal`")
+            .note("an unsuffixed integer value, e.g., `1`, is expected")
+            .emit();
+        None
+    }
+}
+
+fn check_link_name_xor_ordinal(
+    tcx: TyCtxt<'_>,
+    codegen_fn_attrs: &CodegenFnAttrs,
+    inline_span: Option<Span>,
+) {
+    if codegen_fn_attrs.link_name.is_none() || codegen_fn_attrs.link_ordinal.is_none() {
+        return;
+    }
+    let msg = "cannot use `#[link_name]` with `#[link_ordinal]`";
+    if let Some(span) = inline_span {
+        tcx.sess.span_err(span, msg);
+    } else {
+        tcx.sess.err(msg);
+    }
+}
+
+pub fn provide(providers: &mut Providers) {
+    *providers = Providers { codegen_fn_attrs, should_inherit_track_caller, ..*providers };
+}
diff --git a/compiler/rustc_codegen_ssa/src/common.rs b/compiler/rustc_codegen_ssa/src/common.rs
index 71f9179d0..e1abb73a5 100644
--- a/compiler/rustc_codegen_ssa/src/common.rs
+++ b/compiler/rustc_codegen_ssa/src/common.rs
@@ -1,10 +1,8 @@
 #![allow(non_camel_case_types)]
 
-use rustc_errors::struct_span_err;
 use rustc_hir::LangItem;
 use rustc_middle::mir::interpret::ConstValue;
 use rustc_middle::ty::{self, layout::TyAndLayout, Ty, TyCtxt};
-use rustc_session::Session;
 use rustc_span::Span;
 
 use crate::base;
@@ -193,10 +191,6 @@ pub fn shift_mask_val<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
     }
 }
 
-pub fn span_invalid_monomorphization_error(a: &Session, b: Span, c: &str) {
-    struct_span_err!(a, b, E0511, "{}", c).emit();
-}
-
 pub fn asm_const_to_str<'tcx>(
     tcx: TyCtxt<'tcx>,
     sp: Span,
diff --git a/compiler/rustc_codegen_ssa/src/debuginfo/mod.rs b/compiler/rustc_codegen_ssa/src/debuginfo/mod.rs
index 6e3f4f0b8..60e9b40e8 100644
--- a/compiler/rustc_codegen_ssa/src/debuginfo/mod.rs
+++ b/compiler/rustc_codegen_ssa/src/debuginfo/mod.rs
@@ -10,7 +10,7 @@ pub mod type_names;
 /// NOTE: This is somewhat inconsistent right now: For empty enums and enums with a single
 ///       fieldless variant, we generate DW_TAG_struct_type, although a
 ///       DW_TAG_enumeration_type would be a better fit.
-pub fn wants_c_like_enum_debuginfo<'tcx>(enum_type_and_layout: TyAndLayout<'tcx>) -> bool {
+pub fn wants_c_like_enum_debuginfo(enum_type_and_layout: TyAndLayout<'_>) -> bool {
     match enum_type_and_layout.ty.kind() {
         ty::Adt(adt_def, _) => {
             if !adt_def.is_enum() {
diff --git a/compiler/rustc_codegen_ssa/src/debuginfo/type_names.rs b/compiler/rustc_codegen_ssa/src/debuginfo/type_names.rs
index b004fbf85..1599ccbb2 100644
--- a/compiler/rustc_codegen_ssa/src/debuginfo/type_names.rs
+++ b/compiler/rustc_codegen_ssa/src/debuginfo/type_names.rs
@@ -93,6 +93,7 @@ fn push_debuginfo_type_name<'tcx>(
                     Err(e) => {
                         // Computing the layout can still fail here, e.g. if the target architecture
                         // cannot represent the type. See https://github.com/rust-lang/rust/issues/94961.
+                        // FIXME: migrate once `rustc_middle::mir::interpret::InterpError` is translatable.
                         tcx.sess.fatal(&format!("{}", e));
                     }
                 }
@@ -235,7 +236,7 @@ fn push_debuginfo_type_name<'tcx>(
                 let projection_bounds: SmallVec<[_; 4]> = trait_data
                     .projection_bounds()
                     .map(|bound| {
-                        let ExistentialProjection { item_def_id, term, .. } =
+                        let ExistentialProjection { def_id: item_def_id, term, .. } =
                             tcx.erase_late_bound_regions(bound);
                         // FIXME(associated_const_equality): allow for consts here
                         (item_def_id, term.ty().unwrap())
@@ -411,9 +412,8 @@ fn push_debuginfo_type_name<'tcx>(
         ty::Error(_)
         | ty::Infer(_)
         | ty::Placeholder(..)
-        | ty::Projection(..)
+        | ty::Alias(..)
         | ty::Bound(..)
-        | ty::Opaque(..)
         | ty::GeneratorWitness(..) => {
             bug!(
                 "debuginfo: Trying to create type name for \
@@ -510,7 +510,7 @@ pub fn compute_debuginfo_vtable_name<'tcx>(
         visited.clear();
         push_generic_params_internal(tcx, trait_ref.substs, &mut vtable_name, &mut visited);
     } else {
-        vtable_name.push_str("_");
+        vtable_name.push('_');
     }
 
     push_close_angle_bracket(cpp_like_debuginfo, &mut vtable_name);
diff --git a/compiler/rustc_codegen_ssa/src/errors.rs b/compiler/rustc_codegen_ssa/src/errors.rs
index e3b6fbf1b..d81252653 100644
--- a/compiler/rustc_codegen_ssa/src/errors.rs
+++ b/compiler/rustc_codegen_ssa/src/errors.rs
@@ -6,7 +6,9 @@ use rustc_errors::{
     IntoDiagnosticArg,
 };
 use rustc_macros::Diagnostic;
+use rustc_middle::ty::Ty;
 use rustc_span::{Span, Symbol};
+use rustc_type_ir::FloatTy;
 use std::borrow::Cow;
 use std::io::Error;
 use std::path::{Path, PathBuf};
@@ -445,12 +447,6 @@ pub struct LinkerFileStem;
 pub struct StaticLibraryNativeArtifacts;
 
 #[derive(Diagnostic)]
-#[diag(codegen_ssa_native_static_libs)]
-pub struct NativeStaticLibs {
-    pub arguments: String,
-}
-
-#[derive(Diagnostic)]
 #[diag(codegen_ssa_link_script_unavailable)]
 pub struct LinkScriptUnavailable;
 
@@ -548,3 +544,439 @@ pub struct ArchiveBuildFailure {
 pub struct UnknownArchiveKind<'a> {
     pub kind: &'a str,
 }
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_expected_used_symbol)]
+pub struct ExpectedUsedSymbol {
+    #[primary_span]
+    pub span: Span,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_multiple_main_functions)]
+#[help]
+pub struct MultipleMainFunctions {
+    #[primary_span]
+    pub span: Span,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_metadata_object_file_write)]
+pub struct MetadataObjectFileWrite {
+    pub error: Error,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_invalid_windows_subsystem)]
+pub struct InvalidWindowsSubsystem {
+    pub subsystem: Symbol,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_erroneous_constant)]
+pub struct ErroneousConstant {
+    #[primary_span]
+    pub span: Span,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_polymorphic_constant_too_generic)]
+pub struct PolymorphicConstantTooGeneric {
+    #[primary_span]
+    pub span: Span,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_shuffle_indices_evaluation)]
+pub struct ShuffleIndicesEvaluation {
+    #[primary_span]
+    pub span: Span,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_missing_memory_ordering)]
+pub struct MissingMemoryOrdering;
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_unknown_atomic_ordering)]
+pub struct UnknownAtomicOrdering;
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_atomic_compare_exchange)]
+pub struct AtomicCompareExchange;
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_unknown_atomic_operation)]
+pub struct UnknownAtomicOperation;
+
+#[derive(Diagnostic)]
+pub enum InvalidMonomorphization<'tcx> {
+    #[diag(codegen_ssa_invalid_monomorphization_basic_integer_type, code = "E0511")]
+    BasicIntegerType {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        ty: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_basic_float_type, code = "E0511")]
+    BasicFloatType {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        ty: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_float_to_int_unchecked, code = "E0511")]
+    FloatToIntUnchecked {
+        #[primary_span]
+        span: Span,
+        ty: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_floating_point_vector, code = "E0511")]
+    FloatingPointVector {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        f_ty: FloatTy,
+        in_ty: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_floating_point_type, code = "E0511")]
+    FloatingPointType {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        in_ty: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_unrecognized_intrinsic, code = "E0511")]
+    UnrecognizedIntrinsic {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_simd_argument, code = "E0511")]
+    SimdArgument {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        ty: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_simd_input, code = "E0511")]
+    SimdInput {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        ty: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_simd_first, code = "E0511")]
+    SimdFirst {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        ty: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_simd_second, code = "E0511")]
+    SimdSecond {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        ty: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_simd_third, code = "E0511")]
+    SimdThird {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        ty: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_simd_return, code = "E0511")]
+    SimdReturn {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        ty: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_invalid_bitmask, code = "E0511")]
+    InvalidBitmask {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        mask_ty: Ty<'tcx>,
+        expected_int_bits: u64,
+        expected_bytes: u64,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_return_length_input_type, code = "E0511")]
+    ReturnLengthInputType {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        in_len: u64,
+        in_ty: Ty<'tcx>,
+        ret_ty: Ty<'tcx>,
+        out_len: u64,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_second_argument_length, code = "E0511")]
+    SecondArgumentLength {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        in_len: u64,
+        in_ty: Ty<'tcx>,
+        arg_ty: Ty<'tcx>,
+        out_len: u64,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_third_argument_length, code = "E0511")]
+    ThirdArgumentLength {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        in_len: u64,
+        in_ty: Ty<'tcx>,
+        arg_ty: Ty<'tcx>,
+        out_len: u64,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_return_integer_type, code = "E0511")]
+    ReturnIntegerType {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        ret_ty: Ty<'tcx>,
+        out_ty: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_simd_shuffle, code = "E0511")]
+    SimdShuffle {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        ty: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_return_length, code = "E0511")]
+    ReturnLength {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        in_len: u64,
+        ret_ty: Ty<'tcx>,
+        out_len: u64,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_return_element, code = "E0511")]
+    ReturnElement {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        in_elem: Ty<'tcx>,
+        in_ty: Ty<'tcx>,
+        ret_ty: Ty<'tcx>,
+        out_ty: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_shuffle_index_not_constant, code = "E0511")]
+    ShuffleIndexNotConstant {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        arg_idx: u64,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_shuffle_index_out_of_bounds, code = "E0511")]
+    ShuffleIndexOutOfBounds {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        arg_idx: u64,
+        total_len: u128,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_inserted_type, code = "E0511")]
+    InsertedType {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        in_elem: Ty<'tcx>,
+        in_ty: Ty<'tcx>,
+        out_ty: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_return_type, code = "E0511")]
+    ReturnType {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        in_elem: Ty<'tcx>,
+        in_ty: Ty<'tcx>,
+        ret_ty: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_expected_return_type, code = "E0511")]
+    ExpectedReturnType {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        in_ty: Ty<'tcx>,
+        ret_ty: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_mismatched_lengths, code = "E0511")]
+    MismatchedLengths {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        m_len: u64,
+        v_len: u64,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_mask_type, code = "E0511")]
+    MaskType {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        ty: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_vector_argument, code = "E0511")]
+    VectorArgument {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        in_ty: Ty<'tcx>,
+        in_elem: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_cannot_return, code = "E0511")]
+    CannotReturn {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        ret_ty: Ty<'tcx>,
+        expected_int_bits: u64,
+        expected_bytes: u64,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_expected_element_type, code = "E0511")]
+    ExpectedElementType {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        expected_element: Ty<'tcx>,
+        second_arg: Ty<'tcx>,
+        in_elem: Ty<'tcx>,
+        in_ty: Ty<'tcx>,
+        mutability: ExpectedPointerMutability,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_third_arg_element_type, code = "E0511")]
+    ThirdArgElementType {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        expected_element: Ty<'tcx>,
+        third_arg: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_unsupported_symbol_of_size, code = "E0511")]
+    UnsupportedSymbolOfSize {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        symbol: Symbol,
+        in_ty: Ty<'tcx>,
+        in_elem: Ty<'tcx>,
+        size: u64,
+        ret_ty: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_unsupported_symbol, code = "E0511")]
+    UnsupportedSymbol {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        symbol: Symbol,
+        in_ty: Ty<'tcx>,
+        in_elem: Ty<'tcx>,
+        ret_ty: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_cast_fat_pointer, code = "E0511")]
+    CastFatPointer {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        ty: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_expected_pointer, code = "E0511")]
+    ExpectedPointer {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        ty: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_expected_usize, code = "E0511")]
+    ExpectedUsize {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        ty: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_unsupported_cast, code = "E0511")]
+    UnsupportedCast {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        in_ty: Ty<'tcx>,
+        in_elem: Ty<'tcx>,
+        ret_ty: Ty<'tcx>,
+        out_elem: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_unsupported_operation, code = "E0511")]
+    UnsupportedOperation {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        in_ty: Ty<'tcx>,
+        in_elem: Ty<'tcx>,
+    },
+
+    #[diag(codegen_ssa_invalid_monomorphization_expected_vector_element_type, code = "E0511")]
+    ExpectedVectorElementType {
+        #[primary_span]
+        span: Span,
+        name: Symbol,
+        expected_element: Ty<'tcx>,
+        vector_type: Ty<'tcx>,
+    },
+}
+
+pub enum ExpectedPointerMutability {
+    Mut,
+    Not,
+}
+
+impl IntoDiagnosticArg for ExpectedPointerMutability {
+    fn into_diagnostic_arg(self) -> DiagnosticArgValue<'static> {
+        match self {
+            ExpectedPointerMutability::Mut => DiagnosticArgValue::Str(Cow::Borrowed("*mut")),
+            ExpectedPointerMutability::Not => DiagnosticArgValue::Str(Cow::Borrowed("*_")),
+        }
+    }
+}
diff --git a/compiler/rustc_codegen_ssa/src/glue.rs b/compiler/rustc_codegen_ssa/src/glue.rs
index 6015d48de..0f6e6032f 100644
--- a/compiler/rustc_codegen_ssa/src/glue.rs
+++ b/compiler/rustc_codegen_ssa/src/glue.rs
@@ -29,6 +29,9 @@ pub fn size_and_align_of_dst<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
             let align = meth::VirtualIndex::from_index(ty::COMMON_VTABLE_ENTRIES_ALIGN)
                 .get_usize(bx, vtable);
 
+            // Size is always <= isize::MAX.
+            let size_bound = bx.data_layout().ptr_sized_integer().signed_max() as u128;
+            bx.range_metadata(size, WrappingRange { start: 0, end: size_bound });
             // Alignment is always nonzero.
             bx.range_metadata(align, WrappingRange { start: 1, end: !0 });
 
diff --git a/compiler/rustc_codegen_ssa/src/lib.rs b/compiler/rustc_codegen_ssa/src/lib.rs
index def6390f6..0e6596d4b 100644
--- a/compiler/rustc_codegen_ssa/src/lib.rs
+++ b/compiler/rustc_codegen_ssa/src/lib.rs
@@ -42,6 +42,7 @@ use std::path::{Path, PathBuf};
 
 pub mod back;
 pub mod base;
+pub mod codegen_attrs;
 pub mod common;
 pub mod coverageinfo;
 pub mod debuginfo;
@@ -180,6 +181,7 @@ pub fn provide(providers: &mut Providers) {
     crate::back::symbol_export::provide(providers);
     crate::base::provide(providers);
     crate::target_features::provide(providers);
+    crate::codegen_attrs::provide(providers);
 }
 
 pub fn provide_extern(providers: &mut ExternProviders) {
diff --git a/compiler/rustc_codegen_ssa/src/meth.rs b/compiler/rustc_codegen_ssa/src/meth.rs
index cae46ebd2..2421acab4 100644
--- a/compiler/rustc_codegen_ssa/src/meth.rs
+++ b/compiler/rustc_codegen_ssa/src/meth.rs
@@ -31,8 +31,7 @@ impl<'a, 'tcx> VirtualIndex {
             let typeid =
                 bx.typeid_metadata(typeid_for_trait_ref(bx.tcx(), expect_dyn_trait_in_self(ty)));
             let vtable_byte_offset = self.0 * bx.data_layout().pointer_size.bytes();
-            let type_checked_load = bx.type_checked_load(llvtable, vtable_byte_offset, typeid);
-            let func = bx.extract_value(type_checked_load, 0);
+            let func = bx.type_checked_load(llvtable, vtable_byte_offset, typeid);
             bx.pointercast(func, llty)
         } else {
             let ptr_align = bx.tcx().data_layout.pointer_align.abi;
@@ -66,7 +65,7 @@ impl<'a, 'tcx> VirtualIndex {
 
 /// This takes a valid `self` receiver type and extracts the principal trait
 /// ref of the type.
-fn expect_dyn_trait_in_self<'tcx>(ty: Ty<'tcx>) -> ty::PolyExistentialTraitRef<'tcx> {
+fn expect_dyn_trait_in_self(ty: Ty<'_>) -> ty::PolyExistentialTraitRef<'_> {
     for arg in ty.peel_refs().walk() {
         if let GenericArgKind::Type(ty) = arg.unpack() {
             if let ty::Dynamic(data, _, _) = ty.kind() {
diff --git a/compiler/rustc_codegen_ssa/src/mir/analyze.rs b/compiler/rustc_codegen_ssa/src/mir/analyze.rs
index c7617d2e4..dd1ac2c74 100644
--- a/compiler/rustc_codegen_ssa/src/mir/analyze.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/analyze.rs
@@ -261,6 +261,9 @@ impl CleanupKind {
     }
 }
 
+/// MSVC requires unwinding code to be split to a tree of *funclets*, where each funclet can only
+/// branch to itself or to its parent. Luckily, the code we generates matches this pattern.
+/// Recover that structure in an analyze pass.
 pub fn cleanup_kinds(mir: &mir::Body<'_>) -> IndexVec<mir::BasicBlock, CleanupKind> {
     fn discover_masters<'tcx>(
         result: &mut IndexVec<mir::BasicBlock, CleanupKind>,
diff --git a/compiler/rustc_codegen_ssa/src/mir/block.rs b/compiler/rustc_codegen_ssa/src/mir/block.rs
index 03d833fbb..978aff511 100644
--- a/compiler/rustc_codegen_ssa/src/mir/block.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/block.rs
@@ -289,16 +289,13 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
             bx.cleanup_ret(funclet, None);
         } else {
             let slot = self.get_personality_slot(bx);
-            let lp0 = slot.project_field(bx, 0);
-            let lp0 = bx.load_operand(lp0).immediate();
-            let lp1 = slot.project_field(bx, 1);
-            let lp1 = bx.load_operand(lp1).immediate();
+            let exn0 = slot.project_field(bx, 0);
+            let exn0 = bx.load_operand(exn0).immediate();
+            let exn1 = slot.project_field(bx, 1);
+            let exn1 = bx.load_operand(exn1).immediate();
             slot.storage_dead(bx);
 
-            let mut lp = bx.const_undef(self.landing_pad_type());
-            lp = bx.insert_value(lp, lp0, 0);
-            lp = bx.insert_value(lp, lp1, 1);
-            bx.resume(lp);
+            bx.resume(exn0, exn1);
         }
     }
 
@@ -307,12 +304,10 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         helper: TerminatorCodegenHelper<'tcx>,
         bx: &mut Bx,
         discr: &mir::Operand<'tcx>,
-        switch_ty: Ty<'tcx>,
         targets: &SwitchTargets,
     ) {
         let discr = self.codegen_operand(bx, &discr);
-        // `switch_ty` is redundant, sanity-check that.
-        assert_eq!(discr.layout.ty, switch_ty);
+        let switch_ty = discr.layout.ty;
         let mut target_iter = targets.iter();
         if target_iter.len() == 1 {
             // If there are two targets (one conditional, one fallback), emit `br` instead of
@@ -642,7 +637,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         self.set_debug_loc(bx, terminator.source_info);
 
         // Obtain the panic entry point.
-        let (fn_abi, llfn) = common::build_langcall(bx, Some(span), LangItem::PanicNoUnwind);
+        let (fn_abi, llfn) = common::build_langcall(bx, Some(span), LangItem::PanicCannotUnwind);
 
         // Codegen the actual panic invoke/call.
         let merging_succ = helper.do_call(self, bx, fn_abi, llfn, &[], None, None, &[], false);
@@ -668,12 +663,12 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         enum AssertIntrinsic {
             Inhabited,
             ZeroValid,
-            UninitValid,
+            MemUninitializedValid,
         }
         let panic_intrinsic = intrinsic.and_then(|i| match i {
             sym::assert_inhabited => Some(AssertIntrinsic::Inhabited),
             sym::assert_zero_valid => Some(AssertIntrinsic::ZeroValid),
-            sym::assert_uninit_valid => Some(AssertIntrinsic::UninitValid),
+            sym::assert_mem_uninitialized_valid => Some(AssertIntrinsic::MemUninitializedValid),
             _ => None,
         });
         if let Some(intrinsic) = panic_intrinsic {
@@ -684,7 +679,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
             let do_panic = match intrinsic {
                 Inhabited => layout.abi.is_uninhabited(),
                 ZeroValid => !bx.tcx().permits_zero_init(layout),
-                UninitValid => !bx.tcx().permits_uninit_init(layout),
+                MemUninitializedValid => !bx.tcx().permits_uninit_init(layout),
             };
             Some(if do_panic {
                 let msg_str = with_no_visible_paths!({
@@ -703,11 +698,10 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                     })
                 });
                 let msg = bx.const_str(&msg_str);
-                let location = self.get_caller_location(bx, source_info).immediate();
 
                 // Obtain the panic entry point.
                 let (fn_abi, llfn) =
-                    common::build_langcall(bx, Some(source_info.span), LangItem::Panic);
+                    common::build_langcall(bx, Some(source_info.span), LangItem::PanicNounwind);
 
                 // Codegen the actual panic invoke/call.
                 helper.do_call(
@@ -715,7 +709,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                     bx,
                     fn_abi,
                     llfn,
-                    &[msg.0, msg.1, location],
+                    &[msg.0, msg.1],
                     target.as_ref().map(|bb| (ReturnDest::Nothing, *bb)),
                     cleanup,
                     &[],
@@ -753,10 +747,13 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         let (instance, mut llfn) = match *callee.layout.ty.kind() {
             ty::FnDef(def_id, substs) => (
                 Some(
-                    ty::Instance::resolve(bx.tcx(), ty::ParamEnv::reveal_all(), def_id, substs)
-                        .unwrap()
-                        .unwrap()
-                        .polymorphize(bx.tcx()),
+                    ty::Instance::expect_resolve(
+                        bx.tcx(),
+                        ty::ParamEnv::reveal_all(),
+                        def_id,
+                        substs,
+                    )
+                    .polymorphize(bx.tcx()),
                 ),
                 None,
             ),
@@ -1293,8 +1290,8 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                 helper.funclet_br(self, bx, target, mergeable_succ())
             }
 
-            mir::TerminatorKind::SwitchInt { ref discr, switch_ty, ref targets } => {
-                self.codegen_switchint_terminator(helper, bx, discr, switch_ty, targets);
+            mir::TerminatorKind::SwitchInt { ref discr, ref targets } => {
+                self.codegen_switchint_terminator(helper, bx, discr, targets);
                 MergingSucc::False
             }
 
@@ -1635,24 +1632,17 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
             let mut cleanup_bx = Bx::build(self.cx, cleanup_llbb);
 
             let llpersonality = self.cx.eh_personality();
-            let llretty = self.landing_pad_type();
-            let lp = cleanup_bx.cleanup_landing_pad(llretty, llpersonality);
+            let (exn0, exn1) = cleanup_bx.cleanup_landing_pad(llpersonality);
 
             let slot = self.get_personality_slot(&mut cleanup_bx);
             slot.storage_live(&mut cleanup_bx);
-            Pair(cleanup_bx.extract_value(lp, 0), cleanup_bx.extract_value(lp, 1))
-                .store(&mut cleanup_bx, slot);
+            Pair(exn0, exn1).store(&mut cleanup_bx, slot);
 
             cleanup_bx.br(llbb);
             cleanup_llbb
         }
     }
 
-    fn landing_pad_type(&self) -> Bx::Type {
-        let cx = self.cx;
-        cx.type_struct(&[cx.type_i8p(), cx.type_i32()], false)
-    }
-
     fn unreachable_block(&mut self) -> Bx::BasicBlock {
         self.unreachable_block.unwrap_or_else(|| {
             let llbb = Bx::append_block(self.cx, self.llfn, "unreachable");
@@ -1672,10 +1662,9 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
             self.set_debug_loc(&mut bx, mir::SourceInfo::outermost(self.mir.span));
 
             let llpersonality = self.cx.eh_personality();
-            let llretty = self.landing_pad_type();
-            bx.cleanup_landing_pad(llretty, llpersonality);
+            bx.cleanup_landing_pad(llpersonality);
 
-            let (fn_abi, fn_ptr) = common::build_langcall(&bx, None, LangItem::PanicNoUnwind);
+            let (fn_abi, fn_ptr) = common::build_langcall(&bx, None, LangItem::PanicCannotUnwind);
             let fn_ty = bx.fn_decl_backend_type(&fn_abi);
 
             let llret = bx.call(fn_ty, Some(&fn_abi), fn_ptr, &[], None);
@@ -1812,15 +1801,20 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         match (src.layout.abi, dst.layout.abi) {
             (abi::Abi::Scalar(src_scalar), abi::Abi::Scalar(dst_scalar)) => {
                 // HACK(eddyb) LLVM doesn't like `bitcast`s between pointers and non-pointers.
-                if (src_scalar.primitive() == abi::Pointer)
-                    == (dst_scalar.primitive() == abi::Pointer)
-                {
+                let src_is_ptr = src_scalar.primitive() == abi::Pointer;
+                let dst_is_ptr = dst_scalar.primitive() == abi::Pointer;
+                if src_is_ptr == dst_is_ptr {
                     assert_eq!(src.layout.size, dst.layout.size);
 
                     // NOTE(eddyb) the `from_immediate` and `to_immediate_scalar`
                     // conversions allow handling `bool`s the same as `u8`s.
                     let src = bx.from_immediate(src.immediate());
-                    let src_as_dst = bx.bitcast(src, bx.backend_type(dst.layout));
+                    // LLVM also doesn't like `bitcast`s between pointers in different address spaces.
+                    let src_as_dst = if src_is_ptr {
+                        bx.pointercast(src, bx.backend_type(dst.layout))
+                    } else {
+                        bx.bitcast(src, bx.backend_type(dst.layout))
+                    };
                     Immediate(bx.to_immediate_scalar(src_as_dst, dst_scalar)).store(bx, dst);
                     return;
                 }
diff --git a/compiler/rustc_codegen_ssa/src/mir/constant.rs b/compiler/rustc_codegen_ssa/src/mir/constant.rs
index 53ff3c240..14fe84a14 100644
--- a/compiler/rustc_codegen_ssa/src/mir/constant.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/constant.rs
@@ -1,3 +1,4 @@
+use crate::errors;
 use crate::mir::operand::OperandRef;
 use crate::traits::*;
 use rustc_middle::mir;
@@ -44,10 +45,14 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         self.cx.tcx().const_eval_resolve(ty::ParamEnv::reveal_all(), uv, None).map_err(|err| {
             match err {
                 ErrorHandled::Reported(_) => {
-                    self.cx.tcx().sess.span_err(constant.span, "erroneous constant encountered");
+                    self.cx.tcx().sess.emit_err(errors::ErroneousConstant { span: constant.span });
                 }
                 ErrorHandled::TooGeneric => {
-                    span_bug!(constant.span, "codegen encountered polymorphic constant: {:?}", err);
+                    self.cx
+                        .tcx()
+                        .sess
+                        .diagnostic()
+                        .emit_bug(errors::PolymorphicConstantTooGeneric { span: constant.span });
                 }
             }
             err
@@ -87,7 +92,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                 (llval, c.ty())
             })
             .unwrap_or_else(|_| {
-                bx.tcx().sess.span_err(span, "could not evaluate shuffle_indices at compile time");
+                bx.tcx().sess.emit_err(errors::ShuffleIndicesEvaluation { span });
                 // We've errored, so we don't have to produce working code.
                 let ty = self.monomorphize(ty);
                 let llty = bx.backend_type(bx.layout_of(ty));
diff --git a/compiler/rustc_codegen_ssa/src/mir/debuginfo.rs b/compiler/rustc_codegen_ssa/src/mir/debuginfo.rs
index 99283d3bb..e9bc40c33 100644
--- a/compiler/rustc_codegen_ssa/src/mir/debuginfo.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/debuginfo.rs
@@ -3,12 +3,12 @@ use rustc_index::vec::IndexVec;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
 use rustc_middle::mir;
 use rustc_middle::ty;
+use rustc_middle::ty::layout::TyAndLayout;
 use rustc_middle::ty::layout::{HasTyCtxt, LayoutOf};
 use rustc_session::config::DebugInfo;
 use rustc_span::symbol::{kw, Symbol};
 use rustc_span::{BytePos, Span};
-use rustc_target::abi::Abi;
-use rustc_target::abi::Size;
+use rustc_target::abi::{Abi, Size, VariantIdx};
 
 use super::operand::{OperandRef, OperandValue};
 use super::place::PlaceRef;
@@ -57,9 +57,9 @@ pub struct DebugScope<S, L> {
 }
 
 impl<'tcx, S: Copy, L: Copy> DebugScope<S, L> {
-    /// DILocations inherit source file name from the parent DIScope.  Due to macro expansions
+    /// DILocations inherit source file name from the parent DIScope. Due to macro expansions
     /// it may so happen that the current span belongs to a different file than the DIScope
-    /// corresponding to span's containing source scope.  If so, we need to create a DIScope
+    /// corresponding to span's containing source scope. If so, we need to create a DIScope
     /// "extension" into that file.
     pub fn adjust_dbg_scope_for_span<Cx: CodegenMethods<'tcx, DIScope = S, DILocation = L>>(
         &self,
@@ -76,6 +76,106 @@ impl<'tcx, S: Copy, L: Copy> DebugScope<S, L> {
     }
 }
 
+trait DebugInfoOffsetLocation<'tcx, Bx> {
+    fn deref(&self, bx: &mut Bx) -> Self;
+    fn layout(&self) -> TyAndLayout<'tcx>;
+    fn project_field(&self, bx: &mut Bx, field: mir::Field) -> Self;
+    fn downcast(&self, bx: &mut Bx, variant: VariantIdx) -> Self;
+}
+
+impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> DebugInfoOffsetLocation<'tcx, Bx>
+    for PlaceRef<'tcx, Bx::Value>
+{
+    fn deref(&self, bx: &mut Bx) -> Self {
+        bx.load_operand(*self).deref(bx.cx())
+    }
+
+    fn layout(&self) -> TyAndLayout<'tcx> {
+        self.layout
+    }
+
+    fn project_field(&self, bx: &mut Bx, field: mir::Field) -> Self {
+        PlaceRef::project_field(*self, bx, field.index())
+    }
+
+    fn downcast(&self, bx: &mut Bx, variant: VariantIdx) -> Self {
+        self.project_downcast(bx, variant)
+    }
+}
+
+impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> DebugInfoOffsetLocation<'tcx, Bx>
+    for TyAndLayout<'tcx>
+{
+    fn deref(&self, bx: &mut Bx) -> Self {
+        bx.cx().layout_of(
+            self.ty.builtin_deref(true).unwrap_or_else(|| bug!("cannot deref `{}`", self.ty)).ty,
+        )
+    }
+
+    fn layout(&self) -> TyAndLayout<'tcx> {
+        *self
+    }
+
+    fn project_field(&self, bx: &mut Bx, field: mir::Field) -> Self {
+        self.field(bx.cx(), field.index())
+    }
+
+    fn downcast(&self, bx: &mut Bx, variant: VariantIdx) -> Self {
+        self.for_variant(bx.cx(), variant)
+    }
+}
+
+struct DebugInfoOffset<T> {
+    /// Offset from the `base` used to calculate the debuginfo offset.
+    direct_offset: Size,
+    /// Each offset in this vector indicates one level of indirection from the base or previous
+    /// indirect offset plus a dereference.
+    indirect_offsets: Vec<Size>,
+    /// The final location debuginfo should point to.
+    result: T,
+}
+
+fn calculate_debuginfo_offset<
+    'a,
+    'tcx,
+    Bx: BuilderMethods<'a, 'tcx>,
+    L: DebugInfoOffsetLocation<'tcx, Bx>,
+>(
+    bx: &mut Bx,
+    local: mir::Local,
+    var: &PerLocalVarDebugInfo<'tcx, Bx::DIVariable>,
+    base: L,
+) -> DebugInfoOffset<L> {
+    let mut direct_offset = Size::ZERO;
+    // FIXME(eddyb) use smallvec here.
+    let mut indirect_offsets = vec![];
+    let mut place = base;
+
+    for elem in &var.projection[..] {
+        match *elem {
+            mir::ProjectionElem::Deref => {
+                indirect_offsets.push(Size::ZERO);
+                place = place.deref(bx);
+            }
+            mir::ProjectionElem::Field(field, _) => {
+                let offset = indirect_offsets.last_mut().unwrap_or(&mut direct_offset);
+                *offset += place.layout().fields.offset(field.index());
+                place = place.project_field(bx, field);
+            }
+            mir::ProjectionElem::Downcast(_, variant) => {
+                place = place.downcast(bx, variant);
+            }
+            _ => span_bug!(
+                var.source_info.span,
+                "unsupported var debuginfo place `{:?}`",
+                mir::Place { local, projection: var.projection },
+            ),
+        }
+    }
+
+    DebugInfoOffset { direct_offset, indirect_offsets, result: place }
+}
+
 impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
     pub fn set_debug_loc(&self, bx: &mut Bx, source_info: mir::SourceInfo) {
         bx.set_span(source_info.span);
@@ -262,33 +362,8 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
             let Some(dbg_var) = var.dbg_var else { continue };
             let Some(dbg_loc) = self.dbg_loc(var.source_info) else { continue };
 
-            let mut direct_offset = Size::ZERO;
-            // FIXME(eddyb) use smallvec here.
-            let mut indirect_offsets = vec![];
-            let mut place = base;
-
-            for elem in &var.projection[..] {
-                match *elem {
-                    mir::ProjectionElem::Deref => {
-                        indirect_offsets.push(Size::ZERO);
-                        place = bx.load_operand(place).deref(bx.cx());
-                    }
-                    mir::ProjectionElem::Field(field, _) => {
-                        let i = field.index();
-                        let offset = indirect_offsets.last_mut().unwrap_or(&mut direct_offset);
-                        *offset += place.layout.fields.offset(i);
-                        place = place.project_field(bx, i);
-                    }
-                    mir::ProjectionElem::Downcast(_, variant) => {
-                        place = place.project_downcast(bx, variant);
-                    }
-                    _ => span_bug!(
-                        var.source_info.span,
-                        "unsupported var debuginfo place `{:?}`",
-                        mir::Place { local, projection: var.projection },
-                    ),
-                }
-            }
+            let DebugInfoOffset { direct_offset, indirect_offsets, result: _ } =
+                calculate_debuginfo_offset(bx, local, &var, base.layout);
 
             // When targeting MSVC, create extra allocas for arguments instead of pointing multiple
             // dbg_var_addr() calls into the same alloca with offsets. MSVC uses CodeView records
@@ -306,6 +381,9 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                     || !matches!(&indirect_offsets[..], [Size::ZERO] | []));
 
             if should_create_individual_allocas {
+                let DebugInfoOffset { direct_offset: _, indirect_offsets: _, result: place } =
+                    calculate_debuginfo_offset(bx, local, &var, base);
+
                 // Create a variable which will be a pointer to the actual value
                 let ptr_ty = bx.tcx().mk_ty(ty::RawPtr(ty::TypeAndMut {
                     mutbl: mir::Mutability::Mut,
diff --git a/compiler/rustc_codegen_ssa/src/mir/intrinsic.rs b/compiler/rustc_codegen_ssa/src/mir/intrinsic.rs
index 215edbe02..766dc74cb 100644
--- a/compiler/rustc_codegen_ssa/src/mir/intrinsic.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/intrinsic.rs
@@ -1,7 +1,9 @@
 use super::operand::{OperandRef, OperandValue};
 use super::place::PlaceRef;
 use super::FunctionCx;
-use crate::common::{span_invalid_monomorphization_error, IntPredicate};
+use crate::common::IntPredicate;
+use crate::errors;
+use crate::errors::InvalidMonomorphization;
 use crate::glue;
 use crate::meth;
 use crate::traits::*;
@@ -110,10 +112,16 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                     _ => bug!(),
                 };
                 let value = meth::VirtualIndex::from_index(idx).get_usize(bx, vtable);
-                if name == sym::vtable_align {
+                match name {
+                    // Size is always <= isize::MAX.
+                    sym::vtable_size => {
+                        let size_bound = bx.data_layout().ptr_sized_integer().signed_max() as u128;
+                        bx.range_metadata(value, WrappingRange { start: 0, end: size_bound });
+                    },
                     // Alignment is always nonzero.
-                    bx.range_metadata(value, WrappingRange { start: 1, end: !0 });
-                };
+                    sym::vtable_align => bx.range_metadata(value, WrappingRange { start: 1, end: !0 }),
+                    _ => {}
+                }
                 value
             }
             sym::pref_align_of
@@ -299,15 +307,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                         _ => bug!(),
                     },
                     None => {
-                        span_invalid_monomorphization_error(
-                            bx.tcx().sess,
-                            span,
-                            &format!(
-                                "invalid monomorphization of `{}` intrinsic: \
-                                      expected basic integer type, found `{}`",
-                                name, ty
-                            ),
-                        );
+                        bx.tcx().sess.emit_err(InvalidMonomorphization::BasicIntegerType { span, name, ty });
                         return;
                     }
                 }
@@ -323,15 +323,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                         _ => bug!(),
                     },
                     None => {
-                        span_invalid_monomorphization_error(
-                            bx.tcx().sess,
-                            span,
-                            &format!(
-                                "invalid monomorphization of `{}` intrinsic: \
-                                      expected basic float type, found `{}`",
-                                name, arg_tys[0]
-                            ),
-                        );
+                        bx.tcx().sess.emit_err(InvalidMonomorphization::BasicFloatType { span, name, ty: arg_tys[0] });
                         return;
                     }
                 }
@@ -339,29 +331,11 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
 
             sym::float_to_int_unchecked => {
                 if float_type_width(arg_tys[0]).is_none() {
-                    span_invalid_monomorphization_error(
-                        bx.tcx().sess,
-                        span,
-                        &format!(
-                            "invalid monomorphization of `float_to_int_unchecked` \
-                                  intrinsic: expected basic float type, \
-                                  found `{}`",
-                            arg_tys[0]
-                        ),
-                    );
+                    bx.tcx().sess.emit_err(InvalidMonomorphization::FloatToIntUnchecked { span, ty: arg_tys[0] });
                     return;
                 }
                 let Some((_width, signed)) = int_type_width_signed(ret_ty, bx.tcx()) else {
-                    span_invalid_monomorphization_error(
-                        bx.tcx().sess,
-                        span,
-                        &format!(
-                            "invalid monomorphization of `float_to_int_unchecked` \
-                                    intrinsic:  expected basic integer type, \
-                                    found `{}`",
-                            ret_ty
-                        ),
-                    );
+                    bx.tcx().sess.emit_err(InvalidMonomorphization::FloatToIntUnchecked { span, ty: ret_ty });
                     return;
                 };
                 if signed {
@@ -396,7 +370,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                 use crate::common::{AtomicRmwBinOp, SynchronizationScope};
 
                 let Some((instruction, ordering)) = atomic.split_once('_') else {
-                    bx.sess().fatal("Atomic intrinsic missing memory ordering");
+                    bx.sess().emit_fatal(errors::MissingMemoryOrdering);
                 };
 
                 let parse_ordering = |bx: &Bx, s| match s {
@@ -406,25 +380,17 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                     "release" => Release,
                     "acqrel" => AcquireRelease,
                     "seqcst" => SequentiallyConsistent,
-                    _ => bx.sess().fatal("unknown ordering in atomic intrinsic"),
+                    _ => bx.sess().emit_fatal(errors::UnknownAtomicOrdering),
                 };
 
                 let invalid_monomorphization = |ty| {
-                    span_invalid_monomorphization_error(
-                        bx.tcx().sess,
-                        span,
-                        &format!(
-                            "invalid monomorphization of `{}` intrinsic: \
-                                  expected basic integer type, found `{}`",
-                            name, ty
-                        ),
-                    );
+                    bx.tcx().sess.emit_err(InvalidMonomorphization::BasicIntegerType { span, name, ty });
                 };
 
                 match instruction {
                     "cxchg" | "cxchgweak" => {
                         let Some((success, failure)) = ordering.split_once('_') else {
-                            bx.sess().fatal("Atomic compare-exchange intrinsic missing failure memory ordering");
+                            bx.sess().emit_fatal(errors::AtomicCompareExchange);
                         };
                         let ty = substs.type_at(0);
                         if int_type_width_signed(ty, bx.tcx()).is_some() || ty.is_unsafe_ptr() {
@@ -523,7 +489,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                             "min" => AtomicRmwBinOp::AtomicMin,
                             "umax" => AtomicRmwBinOp::AtomicUMax,
                             "umin" => AtomicRmwBinOp::AtomicUMin,
-                            _ => bx.sess().fatal("unknown atomic operation"),
+                            _ => bx.sess().emit_fatal(errors::UnknownAtomicOperation),
                         };
 
                         let ty = substs.type_at(0);
diff --git a/compiler/rustc_codegen_ssa/src/mir/rvalue.rs b/compiler/rustc_codegen_ssa/src/mir/rvalue.rs
index 9ad96f7a4..23196c8cb 100644
--- a/compiler/rustc_codegen_ssa/src/mir/rvalue.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/rvalue.rs
@@ -462,7 +462,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                 assert!(bx.cx().tcx().is_static(def_id));
                 let static_ = bx.get_static(def_id);
                 let layout = bx.layout_of(bx.cx().tcx().static_ptr_ty(def_id));
-                OperandRef::from_immediate_or_packed_pair(bx, static_, layout)
+                OperandRef { val: OperandValue::Immediate(static_), layout }
             }
             mir::Rvalue::Use(ref operand) => self.codegen_operand(bx, operand),
             mir::Rvalue::Repeat(..) | mir::Rvalue::Aggregate(..) => {
diff --git a/compiler/rustc_codegen_ssa/src/target_features.rs b/compiler/rustc_codegen_ssa/src/target_features.rs
index 301683e8e..739963fff 100644
--- a/compiler/rustc_codegen_ssa/src/target_features.rs
+++ b/compiler/rustc_codegen_ssa/src/target_features.rs
@@ -1,8 +1,19 @@
+use rustc_ast::ast;
+use rustc_attr::InstructionSetAttr;
+use rustc_data_structures::fx::FxHashMap;
+use rustc_data_structures::fx::FxHashSet;
+use rustc_errors::Applicability;
+use rustc_hir as hir;
+use rustc_hir::def_id::DefId;
+use rustc_hir::def_id::LocalDefId;
 use rustc_hir::def_id::LOCAL_CRATE;
 use rustc_middle::ty::query::Providers;
+use rustc_middle::ty::TyCtxt;
+use rustc_session::parse::feature_err;
 use rustc_session::Session;
 use rustc_span::symbol::sym;
 use rustc_span::symbol::Symbol;
+use rustc_span::Span;
 
 /// Features that control behaviour of rustc, rather than the codegen.
 pub const RUSTC_SPECIFIC_FEATURES: &[&str] = &["crt-static"];
@@ -176,7 +187,7 @@ const X86_ALLOWED_FEATURES: &[(&str, Option<Symbol>)] = &[
     ("bmi2", None),
     ("cmpxchg16b", Some(sym::cmpxchg16b_target_feature)),
     ("ermsb", Some(sym::ermsb_target_feature)),
-    ("f16c", Some(sym::f16c_target_feature)),
+    ("f16c", None),
     ("fma", None),
     ("fxsr", None),
     ("gfni", Some(sym::avx512_target_feature)),
@@ -322,15 +333,147 @@ pub fn tied_target_features(sess: &Session) -> &'static [&'static [&'static str]
     }
 }
 
-pub(crate) fn provide(providers: &mut Providers) {
-    providers.supported_target_features = |tcx, cnum| {
-        assert_eq!(cnum, LOCAL_CRATE);
-        if tcx.sess.opts.actually_rustdoc {
-            // rustdoc needs to be able to document functions that use all the features, so
-            // whitelist them all
-            all_known_features().map(|(a, b)| (a.to_string(), b)).collect()
-        } else {
-            supported_target_features(tcx.sess).iter().map(|&(a, b)| (a.to_string(), b)).collect()
-        }
+pub fn from_target_feature(
+    tcx: TyCtxt<'_>,
+    attr: &ast::Attribute,
+    supported_target_features: &FxHashMap<String, Option<Symbol>>,
+    target_features: &mut Vec<Symbol>,
+) {
+    let Some(list) = attr.meta_item_list() else { return };
+    let bad_item = |span| {
+        let msg = "malformed `target_feature` attribute input";
+        let code = "enable = \"..\"";
+        tcx.sess
+            .struct_span_err(span, msg)
+            .span_suggestion(span, "must be of the form", code, Applicability::HasPlaceholders)
+            .emit();
     };
+    let rust_features = tcx.features();
+    for item in list {
+        // Only `enable = ...` is accepted in the meta-item list.
+        if !item.has_name(sym::enable) {
+            bad_item(item.span());
+            continue;
+        }
+
+        // Must be of the form `enable = "..."` (a string).
+        let Some(value) = item.value_str() else {
+            bad_item(item.span());
+            continue;
+        };
+
+        // We allow comma separation to enable multiple features.
+        target_features.extend(value.as_str().split(',').filter_map(|feature| {
+            let Some(feature_gate) = supported_target_features.get(feature) else {
+                let msg =
+                    format!("the feature named `{}` is not valid for this target", feature);
+                let mut err = tcx.sess.struct_span_err(item.span(), &msg);
+                err.span_label(
+                    item.span(),
+                    format!("`{}` is not valid for this target", feature),
+                );
+                if let Some(stripped) = feature.strip_prefix('+') {
+                    let valid = supported_target_features.contains_key(stripped);
+                    if valid {
+                        err.help("consider removing the leading `+` in the feature name");
+                    }
+                }
+                err.emit();
+                return None;
+            };
+
+            // Only allow features whose feature gates have been enabled.
+            let allowed = match feature_gate.as_ref().copied() {
+                Some(sym::arm_target_feature) => rust_features.arm_target_feature,
+                Some(sym::hexagon_target_feature) => rust_features.hexagon_target_feature,
+                Some(sym::powerpc_target_feature) => rust_features.powerpc_target_feature,
+                Some(sym::mips_target_feature) => rust_features.mips_target_feature,
+                Some(sym::riscv_target_feature) => rust_features.riscv_target_feature,
+                Some(sym::avx512_target_feature) => rust_features.avx512_target_feature,
+                Some(sym::sse4a_target_feature) => rust_features.sse4a_target_feature,
+                Some(sym::tbm_target_feature) => rust_features.tbm_target_feature,
+                Some(sym::wasm_target_feature) => rust_features.wasm_target_feature,
+                Some(sym::cmpxchg16b_target_feature) => rust_features.cmpxchg16b_target_feature,
+                Some(sym::movbe_target_feature) => rust_features.movbe_target_feature,
+                Some(sym::rtm_target_feature) => rust_features.rtm_target_feature,
+                Some(sym::ermsb_target_feature) => rust_features.ermsb_target_feature,
+                Some(sym::bpf_target_feature) => rust_features.bpf_target_feature,
+                Some(sym::aarch64_ver_target_feature) => rust_features.aarch64_ver_target_feature,
+                Some(name) => bug!("unknown target feature gate {}", name),
+                None => true,
+            };
+            if !allowed {
+                feature_err(
+                    &tcx.sess.parse_sess,
+                    feature_gate.unwrap(),
+                    item.span(),
+                    &format!("the target feature `{}` is currently unstable", feature),
+                )
+                .emit();
+            }
+            Some(Symbol::intern(feature))
+        }));
+    }
+}
+
+/// Computes the set of target features used in a function for the purposes of
+/// inline assembly.
+fn asm_target_features(tcx: TyCtxt<'_>, did: DefId) -> &FxHashSet<Symbol> {
+    let mut target_features = tcx.sess.unstable_target_features.clone();
+    if tcx.def_kind(did).has_codegen_attrs() {
+        let attrs = tcx.codegen_fn_attrs(did);
+        target_features.extend(&attrs.target_features);
+        match attrs.instruction_set {
+            None => {}
+            Some(InstructionSetAttr::ArmA32) => {
+                target_features.remove(&sym::thumb_mode);
+            }
+            Some(InstructionSetAttr::ArmT32) => {
+                target_features.insert(sym::thumb_mode);
+            }
+        }
+    }
+
+    tcx.arena.alloc(target_features)
+}
+
+/// Checks the function annotated with `#[target_feature]` is not a safe
+/// trait method implementation, reporting an error if it is.
+pub fn check_target_feature_trait_unsafe(tcx: TyCtxt<'_>, id: LocalDefId, attr_span: Span) {
+    let hir_id = tcx.hir().local_def_id_to_hir_id(id);
+    let node = tcx.hir().get(hir_id);
+    if let hir::Node::ImplItem(hir::ImplItem { kind: hir::ImplItemKind::Fn(..), .. }) = node {
+        let parent_id = tcx.hir().get_parent_item(hir_id);
+        let parent_item = tcx.hir().expect_item(parent_id.def_id);
+        if let hir::ItemKind::Impl(hir::Impl { of_trait: Some(_), .. }) = parent_item.kind {
+            tcx.sess
+                .struct_span_err(
+                    attr_span,
+                    "`#[target_feature(..)]` cannot be applied to safe trait method",
+                )
+                .span_label(attr_span, "cannot be applied to safe trait method")
+                .span_label(tcx.def_span(id), "not an `unsafe` function")
+                .emit();
+        }
+    }
+}
+
+pub(crate) fn provide(providers: &mut Providers) {
+    *providers = Providers {
+        supported_target_features: |tcx, cnum| {
+            assert_eq!(cnum, LOCAL_CRATE);
+            if tcx.sess.opts.actually_rustdoc {
+                // rustdoc needs to be able to document functions that use all the features, so
+                // whitelist them all
+                all_known_features().map(|(a, b)| (a.to_string(), b)).collect()
+            } else {
+                supported_target_features(tcx.sess)
+                    .iter()
+                    .map(|&(a, b)| (a.to_string(), b))
+                    .collect()
+            }
+        },
+        asm_target_features,
+        ..*providers
+    }
 }
diff --git a/compiler/rustc_codegen_ssa/src/traits/builder.rs b/compiler/rustc_codegen_ssa/src/traits/builder.rs
index bc679a5dc..194768d94 100644
--- a/compiler/rustc_codegen_ssa/src/traits/builder.rs
+++ b/compiler/rustc_codegen_ssa/src/traits/builder.rs
@@ -271,8 +271,8 @@ pub trait BuilderMethods<'a, 'tcx>:
     fn set_personality_fn(&mut self, personality: Self::Value);
 
     // These are used by everyone except msvc
-    fn cleanup_landing_pad(&mut self, ty: Self::Type, pers_fn: Self::Value) -> Self::Value;
-    fn resume(&mut self, exn: Self::Value);
+    fn cleanup_landing_pad(&mut self, pers_fn: Self::Value) -> (Self::Value, Self::Value);
+    fn resume(&mut self, exn0: Self::Value, exn1: Self::Value);
 
     // These are used only by msvc
     fn cleanup_pad(&mut self, parent: Option<Self::Value>, args: &[Self::Value]) -> Self::Funclet;
diff --git a/compiler/rustc_codegen_ssa/src/traits/type_.rs b/compiler/rustc_codegen_ssa/src/traits/type_.rs
index 86481d5d7..109161ccc 100644
--- a/compiler/rustc_codegen_ssa/src/traits/type_.rs
+++ b/compiler/rustc_codegen_ssa/src/traits/type_.rs
@@ -122,6 +122,7 @@ pub trait LayoutTypeMethods<'tcx>: Backend<'tcx> {
 pub trait TypeMembershipMethods<'tcx>: Backend<'tcx> {
     fn set_type_metadata(&self, function: Self::Function, typeid: String);
     fn typeid_metadata(&self, typeid: String) -> Self::Value;
+    fn set_kcfi_type_metadata(&self, function: Self::Function, typeid: u32);
 }
 
 pub trait ArgAbiMethods<'tcx>: HasCodegen<'tcx> {