Author: Timm Baeder Date: 2025-07-04T16:10:12+02:00 New Revision: 258c048f643fff59be15f43f126629a356ef60fa
URL: https://github.com/llvm/llvm-project/commit/258c048f643fff59be15f43f126629a356ef60fa DIFF: https://github.com/llvm/llvm-project/commit/258c048f643fff59be15f43f126629a356ef60fa.diff LOG: [clang][bytecode] Fix copy constructors for empty unions (#147050) Nothing to do in that case. Added: Modified: clang/lib/AST/ByteCode/Compiler.cpp clang/test/AST/ByteCode/unions.cpp Removed: ################################################################################ diff --git a/clang/lib/AST/ByteCode/Compiler.cpp b/clang/lib/AST/ByteCode/Compiler.cpp index 20580c8fe7be3..5ed65f21bb2c0 100644 --- a/clang/lib/AST/ByteCode/Compiler.cpp +++ b/clang/lib/AST/ByteCode/Compiler.cpp @@ -5836,6 +5836,8 @@ bool Compiler<Emitter>::compileConstructor(const CXXConstructorDecl *Ctor) { return false; if (R->isUnion() && Ctor->isCopyOrMoveConstructor()) { + if (R->getNumFields() == 0) + return this->emitRetVoid(Ctor); // union copy and move ctors are special. assert(cast<CompoundStmt>(Ctor->getBody())->body_empty()); if (!this->emitThis(Ctor)) diff --git a/clang/test/AST/ByteCode/unions.cpp b/clang/test/AST/ByteCode/unions.cpp index 36f4b72335af3..0e5f83b9572b3 100644 --- a/clang/test/AST/ByteCode/unions.cpp +++ b/clang/test/AST/ByteCode/unions.cpp @@ -600,6 +600,18 @@ namespace MoveOrAssignOp { } static_assert(foo()); } + +namespace CopyEmptyUnion { + struct A { + union {}; // both-warning {{declaration does not declare anything}} + }; + constexpr int foo() { + A a; + A a2 = a; + return 1; + } + static_assert(foo() == 1); +} #endif namespace AddressComparison { _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
