diff options
Diffstat (limited to 'compiler/rustc_const_eval/src/transform/check_consts/ops.rs')
| -rw-r--r-- | compiler/rustc_const_eval/src/transform/check_consts/ops.rs | 161 |
1 files changed, 56 insertions, 105 deletions
diff --git a/compiler/rustc_const_eval/src/transform/check_consts/ops.rs b/compiler/rustc_const_eval/src/transform/check_consts/ops.rs index 338022616..5fb4bf638 100644 --- a/compiler/rustc_const_eval/src/transform/check_consts/ops.rs +++ b/compiler/rustc_const_eval/src/transform/check_consts/ops.rs @@ -1,6 +1,7 @@ //! Concrete error types for all operations which may be invalid in a certain const context. use hir::def_id::LocalDefId; +use hir::ConstContext; use rustc_errors::{ error_code, struct_span_err, Applicability, DiagnosticBuilder, ErrorGuaranteed, }; @@ -23,8 +24,11 @@ use rustc_trait_selection::traits::SelectionContext; use super::ConstCx; use crate::errors::{ - MutDerefErr, NonConstOpErr, PanicNonStrErr, RawPtrToIntErr, StaticAccessErr, - TransientMutBorrowErr, TransientMutBorrowErrRaw, + InteriorMutabilityBorrow, InteriorMutableDataRefer, MutDerefErr, NonConstFmtMacroCall, + NonConstFnCall, NonConstOpErr, PanicNonStrErr, RawPtrToIntErr, StaticAccessErr, + TransientMutBorrowErr, TransientMutBorrowErrRaw, UnallowedFnPointerCall, + UnallowedHeapAllocations, UnallowedInlineAsm, UnallowedMutableRefs, UnallowedMutableRefsRaw, + UnallowedOpInConstContext, UnstableConstFn, }; use crate::util::{call_kind, CallDesugaringKind, CallKind}; @@ -96,10 +100,7 @@ impl<'tcx> NonConstOp<'tcx> for FnCallIndirect { ccx: &ConstCx<'_, 'tcx>, span: Span, ) -> DiagnosticBuilder<'tcx, ErrorGuaranteed> { - ccx.tcx.sess.struct_span_err( - span, - &format!("function pointer calls are not allowed in {}s", ccx.const_kind()), - ) + ccx.tcx.sess.create_err(UnallowedFnPointerCall { span, kind: ccx.const_kind() }) } } @@ -307,22 +308,13 @@ impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> { err } _ if tcx.opt_parent(callee) == tcx.get_diagnostic_item(sym::ArgumentV1Methods) => { - struct_span_err!( - ccx.tcx.sess, - span, - E0015, - "cannot call non-const formatting macro in {}s", - ccx.const_kind(), - ) + ccx.tcx.sess.create_err(NonConstFmtMacroCall { span, kind: ccx.const_kind() }) } - _ => struct_span_err!( - ccx.tcx.sess, + _ => ccx.tcx.sess.create_err(NonConstFnCall { span, - E0015, - "cannot call non-const fn `{}` in {}s", - ccx.tcx.def_path_str_with_substs(callee, substs), - ccx.const_kind(), - ), + def_path_str: ccx.tcx.def_path_str_with_substs(callee, substs), + kind: ccx.const_kind(), + }), }; err.note(&format!( @@ -331,6 +323,10 @@ impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> { ccx.const_kind(), )); + if let ConstContext::Static(_) = ccx.const_kind() { + err.note("consider wrapping this expression in `Lazy::new(|| ...)` from the `once_cell` crate: https://crates.io/crates/once_cell"); + } + err } } @@ -349,10 +345,10 @@ impl<'tcx> NonConstOp<'tcx> for FnCallUnstable { ) -> DiagnosticBuilder<'tcx, ErrorGuaranteed> { let FnCallUnstable(def_id, feature) = *self; - let mut err = ccx.tcx.sess.struct_span_err( - span, - &format!("`{}` is not yet stable as a const fn", ccx.tcx.def_path_str(def_id)), - ); + let mut err = ccx + .tcx + .sess + .create_err(UnstableConstFn { span, def_path: ccx.tcx.def_path_str(def_id) }); if ccx.is_const_stable_const_fn() { err.help("const-stable functions can only call other const-stable functions"); @@ -387,9 +383,12 @@ impl<'tcx> NonConstOp<'tcx> for Generator { ) -> DiagnosticBuilder<'tcx, ErrorGuaranteed> { let msg = format!("{}s are not allowed in {}s", self.0, ccx.const_kind()); if let hir::GeneratorKind::Async(hir::AsyncGeneratorKind::Block) = self.0 { - feature_err(&ccx.tcx.sess.parse_sess, sym::const_async_blocks, span, &msg) + ccx.tcx.sess.create_feature_err( + UnallowedOpInConstContext { span, msg }, + sym::const_async_blocks, + ) } else { - ccx.tcx.sess.struct_span_err(span, &msg) + ccx.tcx.sess.create_err(UnallowedOpInConstContext { span, msg }) } } } @@ -402,23 +401,11 @@ impl<'tcx> NonConstOp<'tcx> for HeapAllocation { ccx: &ConstCx<'_, 'tcx>, span: Span, ) -> DiagnosticBuilder<'tcx, ErrorGuaranteed> { - let mut err = struct_span_err!( - ccx.tcx.sess, + ccx.tcx.sess.create_err(UnallowedHeapAllocations { span, - E0010, - "allocations are not allowed in {}s", - ccx.const_kind() - ); - err.span_label(span, format!("allocation not allowed in {}s", ccx.const_kind())); - if ccx.tcx.sess.teach(&err.get_code().unwrap()) { - err.note( - "The value of statics and constants must be known at compile time, \ - and they live for the entire lifetime of a program. Creating a boxed \ - value allocates memory on the heap at runtime, and therefore cannot \ - be done at compile time.", - ); - } - err + kind: ccx.const_kind(), + teach: ccx.tcx.sess.teach(&error_code!(E0010)).then_some(()), + }) } } @@ -430,13 +417,7 @@ impl<'tcx> NonConstOp<'tcx> for InlineAsm { ccx: &ConstCx<'_, 'tcx>, span: Span, ) -> DiagnosticBuilder<'tcx, ErrorGuaranteed> { - struct_span_err!( - ccx.tcx.sess, - span, - E0015, - "inline assembly is not allowed in {}s", - ccx.const_kind() - ) + ccx.tcx.sess.create_err(UnallowedInlineAsm { span, kind: ccx.const_kind() }) } } @@ -482,12 +463,7 @@ impl<'tcx> NonConstOp<'tcx> for TransientCellBorrow { ccx: &ConstCx<'_, 'tcx>, span: Span, ) -> DiagnosticBuilder<'tcx, ErrorGuaranteed> { - feature_err( - &ccx.tcx.sess.parse_sess, - sym::const_refs_to_cell, - span, - "cannot borrow here, since the borrowed element may contain interior mutability", - ) + ccx.tcx.sess.create_feature_err(InteriorMutabilityBorrow { span }, sym::const_refs_to_cell) } } @@ -502,32 +478,22 @@ impl<'tcx> NonConstOp<'tcx> for CellBorrow { ccx: &ConstCx<'_, 'tcx>, span: Span, ) -> DiagnosticBuilder<'tcx, ErrorGuaranteed> { - let mut err = struct_span_err!( - ccx.tcx.sess, - span, - E0492, - "{}s cannot refer to interior mutable data", - ccx.const_kind(), - ); - err.span_label( - span, - "this borrow of an interior mutable value may end up in the final value", - ); + // FIXME: Maybe a more elegant solution to this if else case if let hir::ConstContext::Static(_) = ccx.const_kind() { - err.help( - "to fix this, the value can be extracted to a separate \ - `static` item and then referenced", - ); - } - if ccx.tcx.sess.teach(&err.get_code().unwrap()) { - err.note( - "A constant containing interior mutable data behind a reference can allow you - to modify that data. This would make multiple uses of a constant to be able to - see different values and allow circumventing the `Send` and `Sync` requirements - for shared mutable data, which is unsound.", - ); + ccx.tcx.sess.create_err(InteriorMutableDataRefer { + span, + opt_help: Some(()), + kind: ccx.const_kind(), + teach: ccx.tcx.sess.teach(&error_code!(E0492)).then_some(()), + }) + } else { + ccx.tcx.sess.create_err(InteriorMutableDataRefer { + span, + opt_help: None, + kind: ccx.const_kind(), + teach: ccx.tcx.sess.teach(&error_code!(E0492)).then_some(()), + }) } - err } } @@ -553,33 +519,18 @@ impl<'tcx> NonConstOp<'tcx> for MutBorrow { ccx: &ConstCx<'_, 'tcx>, span: Span, ) -> DiagnosticBuilder<'tcx, ErrorGuaranteed> { - let raw = match self.0 { - hir::BorrowKind::Raw => "raw ", - hir::BorrowKind::Ref => "", - }; - - let mut err = struct_span_err!( - ccx.tcx.sess, - span, - E0764, - "{}mutable references are not allowed in the final value of {}s", - raw, - ccx.const_kind(), - ); - - if ccx.tcx.sess.teach(&err.get_code().unwrap()) { - err.note( - "References in statics and constants may only refer \ - to immutable values.\n\n\ - Statics are shared everywhere, and if they refer to \ - mutable data one might violate memory safety since \ - holding multiple mutable references to shared data \ - is not allowed.\n\n\ - If you really want global mutable state, try using \ - static mut or a global UnsafeCell.", - ); + match self.0 { + hir::BorrowKind::Raw => ccx.tcx.sess.create_err(UnallowedMutableRefsRaw { + span, + kind: ccx.const_kind(), + teach: ccx.tcx.sess.teach(&error_code!(E0764)).then_some(()), + }), + hir::BorrowKind::Ref => ccx.tcx.sess.create_err(UnallowedMutableRefs { + span, + kind: ccx.const_kind(), + teach: ccx.tcx.sess.teach(&error_code!(E0764)).then_some(()), + }), } - err } } |