Author: Timm Baeder Date: 2026-10-14T11:05:32+02:00 New Revision: 3afa38c6b8eac95660a4677b1353745c720212e5
URL: https://github.com/llvm/llvm-project/commit/3afa38c6b8eac95660a4677b1353745c720212e5 DIFF: https://github.com/llvm/llvm-project/commit/3afa38c6b8eac95660a4677b1353745c720212e5.diff LOG: [clang][bytecode] Reject invalid opaque pointer base conversions (#231366) We can't reject them as they happen because that needs to work for other tests. So reject them when computing the layout offset. Added: Modified: clang/lib/AST/ByteCode/Interp.h clang/lib/AST/ByteCode/Pointer.cpp clang/test/AST/ByteCode/invalid.cpp Removed: ################################################################################ diff --git a/clang/lib/AST/ByteCode/Interp.h b/clang/lib/AST/ByteCode/Interp.h index ea115b6fef7e3..73f2d415cf56e 100644 --- a/clang/lib/AST/ByteCode/Interp.h +++ b/clang/lib/AST/ByteCode/Interp.h @@ -1343,7 +1343,7 @@ inline bool CmpHelperEQ<Pointer>(InterpState &S, CodePtr OpPC, CompareFn Fn) { std::optional<size_t> A = LHS.computeOffsetForComparison(S.getASTContext()); std::optional<size_t> B = RHS.computeOffsetForComparison(S.getASTContext()); if (!A || !B) - return Invalid(S, OpPC); + return false; S.Stk.push<BoolT>(BoolT::from(Fn(Compare(*A, *B)))); return true; diff --git a/clang/lib/AST/ByteCode/Pointer.cpp b/clang/lib/AST/ByteCode/Pointer.cpp index 6ea2cae2a02ca..839a0929d1852 100644 --- a/clang/lib/AST/ByteCode/Pointer.cpp +++ b/clang/lib/AST/ByteCode/Pointer.cpp @@ -1415,19 +1415,21 @@ OpaquePointer::computeLayoutOffset(const ASTContext &ASTCtx) const { for (const PointerPathEntry &Entry : path()) { switch (Entry.Kind) { case PointerPathEntry::Base: { - const RecordDecl *RD = CurType->getAsRecordDecl(); + const CXXRecordDecl *RD = CurType->getAsCXXRecordDecl(); if (!ASTContext::hasLayout(RD)) return std::nullopt; + const CXXRecordDecl *BaseDecl = Entry.RD.getPointer(); + if (!RD->isDerivedFrom(BaseDecl)) + return std::nullopt; + const ASTRecordLayout &Layout = ASTCtx.getASTRecordLayout(RD); if (Entry.RD.getInt()) - Offset += - Layout.getVBaseClassOffset(Entry.RD.getPointer()).getQuantity(); + Offset += Layout.getVBaseClassOffset(BaseDecl).getQuantity(); else - Offset += - Layout.getBaseClassOffset(Entry.RD.getPointer()).getQuantity(); + Offset += Layout.getBaseClassOffset(BaseDecl).getQuantity(); - CurType = ASTCtx.getCanonicalTagType(Entry.RD.getPointer()); + CurType = ASTCtx.getCanonicalTagType(BaseDecl); } break; case PointerPathEntry::Field: { diff --git a/clang/test/AST/ByteCode/invalid.cpp b/clang/test/AST/ByteCode/invalid.cpp index a160c29169bc5..784fd95baf1dd 100644 --- a/clang/test/AST/ByteCode/invalid.cpp +++ b/clang/test/AST/ByteCode/invalid.cpp @@ -338,3 +338,12 @@ namespace PointerIntoInvalidRecord { } u; template int *foo<&u.baz>; // both-error {{non-type template argument is not a constant expression}} } + +namespace OpaquePtrPtrCast { + struct X {}; + struct Y : X {}; + + constexpr struct Z {} z; + static_assert((X *)(Y *)&z != (X *)(Y *)&z, ""); // both-error {{not an integral constant expression}} \ + // both-note {{cast that performs the conversions of a reinterpret_cast is not allowed in a constant expression}} +} _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
