Author: Chuanqi Xu Date: 2026-03-16T09:05:33Z New Revision: 87f1a2be7505a9f2a2e5179cde36957655ef8d5b
URL: https://github.com/llvm/llvm-project/commit/87f1a2be7505a9f2a2e5179cde36957655ef8d5b DIFF: https://github.com/llvm/llvm-project/commit/87f1a2be7505a9f2a2e5179cde36957655ef8d5b.diff LOG: [C++20] [Modules] Don't add discardable variables to module initializers (#186752) Close https://github.com/llvm/llvm-project/issues/170099 The root cause of the problem is, we shouldn't add the inline variable (which is discardable in linker's point of view) to the module's initializers. I verified with GCC's generated code to make the behavior consistent. This is also a small optimization by the way. Added: clang/test/Modules/pr170099.cppm Modified: clang/lib/Sema/SemaDecl.cpp Removed: ################################################################################ diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp index 054b664ca0a8b..101d5085b980b 100644 --- a/clang/lib/Sema/SemaDecl.cpp +++ b/clang/lib/Sema/SemaDecl.cpp @@ -15138,7 +15138,10 @@ void Sema::CheckCompleteVariableDeclaration(VarDecl *var) { // If this variable must be emitted, add it as an initializer for the current // module. - if (Context.DeclMustBeEmitted(var) && !ModuleScopes.empty()) + if (Context.DeclMustBeEmitted(var) && !ModuleScopes.empty() && + (ModuleScopes.back().Module->isHeaderLikeModule() || + // For named modules, we may only emit non discardable variables. + !isDiscardableGVALinkage(Context.GetGVALinkageForVariable(var)))) Context.addModuleInitializer(ModuleScopes.back().Module, var); // Build the bindings if this is a structured binding declaration. diff --git a/clang/test/Modules/pr170099.cppm b/clang/test/Modules/pr170099.cppm new file mode 100644 index 0000000000000..ca3b4c10fe729 --- /dev/null +++ b/clang/test/Modules/pr170099.cppm @@ -0,0 +1,20 @@ +// RUN: %clang_cc1 -triple %itanium_abi_triple -std=c++26 -O3 -emit-llvm %s -o - | FileCheck %s +module; + +struct A {}; + +struct B { + int x; + A a; + constexpr B(char *) { x = int(); } + ~B(); +}; + +struct C { + B b = ""; +} inline c{}; + +export module foo; + +// Just to make sure it won't crash +// CHECK: @_ZGIW3foo _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
