diff options
| -rw-r--r-- | src/librustc_mir_build/build/mod.rs | 47 |
1 files changed, 42 insertions, 5 deletions
diff --git a/src/librustc_mir_build/build/mod.rs b/src/librustc_mir_build/build/mod.rs index 32b1f2b6e13..5f8c0b027e9 100644 --- a/src/librustc_mir_build/build/mod.rs +++ b/src/librustc_mir_build/build/mod.rs @@ -670,14 +670,51 @@ fn construct_const<'a, 'tcx>( builder.finish() } +/// Construct MIR for a item that has had errors in type checking. +/// +/// This is required because we may still want to run MIR passes on an item +/// with type errors, but normal MIR construction can't handle that in general. fn construct_error<'a, 'tcx>(hir: Cx<'a, 'tcx>, body_id: hir::BodyId) -> Body<'tcx> { - let owner_id = hir.tcx().hir().body_owner(body_id); - let span = hir.tcx().hir().span(owner_id); - let ty = hir.tcx().types.err; - let mut builder = Builder::new(hir, span, 0, Safety::Safe, ty, span, None); + let tcx = hir.tcx(); + let owner_id = tcx.hir().body_owner(body_id); + let span = tcx.hir().span(owner_id); + let ty = tcx.types.err; + let num_params = match hir.body_owner_kind { + hir::BodyOwnerKind::Fn => tcx.hir().fn_decl_by_hir_id(owner_id).unwrap().inputs.len(), + hir::BodyOwnerKind::Closure => { + if tcx.hir().body(body_id).generator_kind().is_some() { + // Generators have an implicit `self` parameter *and* a possibly + // implicit resume parameter. + 2 + } else { + // The implicit self parameter adds another local in MIR. + 1 + tcx.hir().fn_decl_by_hir_id(owner_id).unwrap().inputs.len() + } + } + hir::BodyOwnerKind::Const => 0, + hir::BodyOwnerKind::Static(_) => 0, + }; + let mut builder = Builder::new(hir, span, num_params, Safety::Safe, ty, span, None); let source_info = builder.source_info(span); + // Some MIR passes will expect the number of parameters to match the + // function declaration. + for _ in 0..num_params { + builder.local_decls.push(LocalDecl { + mutability: Mutability::Mut, + ty, + user_ty: UserTypeProjections::none(), + source_info, + internal: false, + local_info: LocalInfo::Other, + is_block_tail: None, + }); + } builder.cfg.terminate(START_BLOCK, source_info, TerminatorKind::Unreachable); - builder.finish() + let mut body = builder.finish(); + if tcx.hir().body(body_id).generator_kind.is_some() { + body.yield_ty = Some(ty); + } + body } impl<'a, 'tcx> Builder<'a, 'tcx> { |