summaryrefslogtreecommitdiffstats
path: root/build/cargo-linker
diff options
context:
space:
mode:
Diffstat (limited to 'build/cargo-linker')
-rwxr-xr-xbuild/cargo-linker65
1 files changed, 65 insertions, 0 deletions
diff --git a/build/cargo-linker b/build/cargo-linker
new file mode 100755
index 0000000000..898e21d482
--- /dev/null
+++ b/build/cargo-linker
@@ -0,0 +1,65 @@
+#!/usr/bin/env python3
+
+# If you want to use a custom linker with Cargo, Cargo requires that you
+# specify it in Cargo.toml or via the matching environment variable.
+# Passing extra options to the linker is possible with Cargo via
+# RUSTFLAGS='-C link-args', but testing showed that doing this reliably
+# was difficult.
+#
+# Our solution to these problems is to use this wrapper script. We pass
+# in the LD and the LDFLAGS to use via environment variables.
+#
+# * MOZ_CARGO_WRAP_LD is equivalent to CC on Unix-y platforms, and CC
+# frequently has additional arguments in addition to the compiler
+# itself.
+#
+# * MOZ_CARGO_WRAP_LDFLAGS contains space-separated arguments to pass,
+# and not quoting it ensures that each of those arguments is passed
+# as a separate argument to the actual LD.
+#
+# * In rare cases, we also need MOZ_CARGO_WRAP_LD_CXX, which is the
+# equivalent of CXX, when linking C++ code. Usually, this should
+# simply work by the use of CC and -lstdc++ (added by cc-rs).
+# However, in the case of sanitizer runtimes, there is a separate
+# runtime for C and C++ and linking C++ code with the C runtime can
+# fail if the requested feature is in the C++ runtime only (bug 1747298).
+
+import os
+import sys
+
+# This is not necessarily run with a virtualenv python, so add
+# the necessary directory for the shellutil module.
+base_dir = os.path.abspath(os.path.dirname(os.path.dirname(__file__)))
+sys.path.insert(0, os.path.join(base_dir, "python", "mozbuild"))
+from mozbuild.shellutil import split
+
+
+SANITIZERS = {
+ "asan": "address",
+ "hwasan": "hwaddress",
+ "lsan": "leak",
+ "msan": "memory",
+ "tsan": "thread",
+}
+
+use_clang_sanitizer = os.environ.get("MOZ_CLANG_NEWER_THAN_RUSTC_LLVM")
+wrap_ld = os.environ["MOZ_CARGO_WRAP_LD"]
+args = split(os.environ["MOZ_CARGO_WRAP_LDFLAGS"])
+for arg in sys.argv[1:]:
+ if arg in ["-lc++", "-lstdc++"]:
+ wrap_ld = os.environ["MOZ_CARGO_WRAP_LD_CXX"]
+ elif use_clang_sanitizer and arg.endswith("san.a"):
+ # When clang is newer than rustc's LLVM, we replace rust's sanitizer
+ # runtimes with clang's.
+ filename = os.path.basename(arg)
+ prefix, dot, suffix = filename[:-2].rpartition(".")
+ if (
+ prefix.startswith("librustc-")
+ and prefix.endswith("_rt") and dot == "."
+ ):
+ args.append(f"-fsanitize={SANITIZERS[suffix]}")
+ continue
+ args.append(arg)
+
+wrap_ld = split(wrap_ld)
+os.execvp(wrap_ld[0], wrap_ld + args)