Author: Timm Baeder Date: 2025-02-05T08:09:13+01:00 New Revision: 16c721f2d1bf5ebbde1b3df103761b45f266a5ec
URL: https://github.com/llvm/llvm-project/commit/16c721f2d1bf5ebbde1b3df103761b45f266a5ec DIFF: https://github.com/llvm/llvm-project/commit/16c721f2d1bf5ebbde1b3df103761b45f266a5ec.diff LOG: [clang][bytecode] Destroy local variables in reverse order (#125727) See the attached test case. Added: Modified: clang/lib/AST/ByteCode/Function.h clang/lib/AST/ByteCode/InterpFrame.cpp clang/test/AST/ByteCode/cxx20.cpp Removed: ################################################################################ diff --git a/clang/lib/AST/ByteCode/Function.h b/clang/lib/AST/ByteCode/Function.h index 2d3421e5e61295..e17183eef9eac6 100644 --- a/clang/lib/AST/ByteCode/Function.h +++ b/clang/lib/AST/ByteCode/Function.h @@ -51,6 +51,11 @@ class Scope final { return llvm::make_range(Descriptors.begin(), Descriptors.end()); } + llvm::iterator_range<LocalVectorTy::const_reverse_iterator> + locals_reverse() const { + return llvm::reverse(Descriptors); + } + private: /// Object descriptors in this block. LocalVectorTy Descriptors; diff --git a/clang/lib/AST/ByteCode/InterpFrame.cpp b/clang/lib/AST/ByteCode/InterpFrame.cpp index 89fc7a4515d641..c383b2bc7f95ce 100644 --- a/clang/lib/AST/ByteCode/InterpFrame.cpp +++ b/clang/lib/AST/ByteCode/InterpFrame.cpp @@ -99,7 +99,7 @@ void InterpFrame::initScope(unsigned Idx) { } void InterpFrame::destroy(unsigned Idx) { - for (auto &Local : Func->getScope(Idx).locals()) { + for (auto &Local : Func->getScope(Idx).locals_reverse()) { S.deallocate(localBlock(Local.Offset)); } } diff --git a/clang/test/AST/ByteCode/cxx20.cpp b/clang/test/AST/ByteCode/cxx20.cpp index 268226a7c143ed..a63aea1ea5548b 100644 --- a/clang/test/AST/ByteCode/cxx20.cpp +++ b/clang/test/AST/ByteCode/cxx20.cpp @@ -908,3 +908,26 @@ namespace TemporaryInNTTP { // expected-note {{created here}} B<2> j2; /// Ok. } + +namespace LocalDestroy { + /// This is reduced from a libc++ test case. + /// The local f.TI.copied points to the local variable Copied, and we used to + /// destroy Copied before f, causing problems later on when a DeadBlock had a + /// pointer pointing to it that was already destroyed. + struct TrackInitialization { + bool *copied_; + }; + struct TrackingPred : TrackInitialization { + constexpr TrackingPred(bool *copied) : TrackInitialization(copied) {} + }; + struct F { + const TrackingPred &TI; + }; + constexpr int f() { + bool Copied = false; + TrackingPred TI(&Copied); + F f{TI}; + return 1; + } + static_assert(f() == 1); +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
