https://github.com/tbaederr created https://github.com/llvm/llvm-project/pull/174317
The original problem description sounded sane but it was lacking a bit. What happens where is that the global block is ultimately not initialized simply because it was already created before and its initializer failed, causing us to call invokeDtor() in a previous evaluation. Check for the initialion state earlier and abort there instead of accessing the (now uninitialized) data of the block, causing msan failures. See the failed msan build at https://lab.llvm.org/buildbot/#/builders/164/builds/17206 >From 3ca6033ccd4b20274f2ab9d5c6c377b42caa2e56 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Timm=20B=C3=A4der?= <[email protected]> Date: Sun, 4 Jan 2026 08:54:35 +0100 Subject: [PATCH] [clang][bytecode] Fix typeid test under msan The original problem description sounded sane but it was lacking a bit. What happens where is that the global block is ultimately not initialized simply because it was already created before and its initializer failed, causing us to call invokeDtor() in a previous evaluation. Check for the initialion state earlier and abort there instead of accessing the (now uninitialized) data of the block, causing msan failures. See the failed msan build at https://lab.llvm.org/buildbot/#/builders/164/builds/17206 --- clang/lib/AST/ByteCode/Compiler.cpp | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/clang/lib/AST/ByteCode/Compiler.cpp b/clang/lib/AST/ByteCode/Compiler.cpp index 4518c587ceca7..f2021ef9456b7 100644 --- a/clang/lib/AST/ByteCode/Compiler.cpp +++ b/clang/lib/AST/ByteCode/Compiler.cpp @@ -4803,8 +4803,7 @@ VarCreationState Compiler<Emitter>::visitDecl(const VarDecl *VD, auto &GD = GlobalBlock->getBlockDesc<GlobalInlineDescriptor>(); GD.InitState = GlobalInitState::InitializerFailed; - if (GlobalBlock->isInitialized()) - GlobalBlock->invokeDtor(); + GlobalBlock->invokeDtor(); } } @@ -4865,8 +4864,7 @@ bool Compiler<Emitter>::visitDeclAndReturn(const VarDecl *VD, const Expr *Init, auto &GD = GlobalBlock->getBlockDesc<GlobalInlineDescriptor>(); GD.InitState = GlobalInitState::InitializerFailed; - if (GlobalBlock->isInitialized()) - GlobalBlock->invokeDtor(); + GlobalBlock->invokeDtor(); } return false; } @@ -4902,8 +4900,11 @@ Compiler<Emitter>::visitVarDecl(const VarDecl *VD, const Expr *Init, UnsignedOrNone GlobalIndex = P.getGlobal(VD); if (GlobalIndex) { + // The global was previously created but the initializer failed. + if (!P.getGlobal(*GlobalIndex)->isInitialized()) + return false; // We've already seen and initialized this global. - if (P.getPtrGlobal(*GlobalIndex).isInitialized()) + if (P.isGlobalInitialized(*GlobalIndex)) return checkDecl(); // The previous attempt at initialization might've been unsuccessful, // so let's try this one. _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
