llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-libcxx <details> <summary>Changes</summary> Fixes #<!-- -->64619 Clang warns diagnostic for non-standard layout types in `offsetof` only if they are in evaluated context. With this patch, you'll also get diagnostic if you use `offsetof` on non-standard layout types in any other contexts --- Full diff: https://github.com/llvm/llvm-project/pull/65246.diff 6 Files Affected: - (modified) clang/docs/ReleaseNotes.rst (+2) - (modified) clang/lib/Sema/SemaExpr.cpp (+4-5) - (modified) clang/test/SemaCXX/class-layout.cpp (+15-15) - (modified) clang/test/SemaCXX/ms_struct.cpp (+3-3) - (modified) clang/test/SemaCXX/offsetof.cpp (+5-4) - (modified) libcxx/include/__type_traits/datasizeof.h (+4) ``````````diff diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index f314c9c72fa28b7..abc36bac05d788d 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -208,6 +208,8 @@ Improvements to Clang's diagnostics (`#54678: <https://github.com/llvm/llvm-project/issues/54678>`_). - Clang now prints its 'note' diagnostic in cyan instead of black, to be more compatible with terminals with dark background colors. This is also more consistent with GCC. +- Clang now always diagnoses when using non-standard layout types in ``offsetof`` . + (`#64619: <https://github.com/llvm/llvm-project/issues/64619>`_) Bug Fixes in This Version ------------------------- diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp index 92496b03ecabe54..fedea932c5e15fe 100644 --- a/clang/lib/Sema/SemaExpr.cpp +++ b/clang/lib/Sema/SemaExpr.cpp @@ -16766,12 +16766,11 @@ ExprResult Sema::BuildBuiltinOffsetOf(SourceLocation BuiltinLoc, LangOpts.CPlusPlus11? diag::ext_offsetof_non_standardlayout_type : diag::ext_offsetof_non_pod_type; - if (!IsSafe && !DidWarnAboutNonPOD && - DiagRuntimeBehavior(BuiltinLoc, nullptr, - PDiag(DiagID) - << SourceRange(Components[0].LocStart, OC.LocEnd) - << CurrentType)) + if (!IsSafe && !DidWarnAboutNonPOD && !isUnevaluatedContext()) { + Diag(BuiltinLoc, DiagID) + << SourceRange(Components[0].LocStart, OC.LocEnd) << CurrentType; DidWarnAboutNonPOD = true; + } } // Look for the field. diff --git a/clang/test/SemaCXX/class-layout.cpp b/clang/test/SemaCXX/class-layout.cpp index 9782ff08100b2d6..23b3dbe24249378 100644 --- a/clang/test/SemaCXX/class-layout.cpp +++ b/clang/test/SemaCXX/class-layout.cpp @@ -1,18 +1,18 @@ -// RUN: %clang_cc1 -triple x86_64-unknown-unknown %s -fsyntax-only -verify -std=c++98 -Wno-inaccessible-base -Wno-c++11-extensions -// RUN: %clang_cc1 -triple x86_64-unknown-unknown %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -// RUN: %clang_cc1 -triple x86_64-apple-darwin %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -DCLANG_ABI_COMPAT=15 -// RUN: %clang_cc1 -triple x86_64-scei-ps4 %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -DCLANG_ABI_COMPAT=6 -// RUN: %clang_cc1 -triple x86_64-sie-ps5 %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -DCLANG_ABI_COMPAT=6 -// RUN: %clang_cc1 -triple x86_64-unknown-unknown %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -fclang-abi-compat=6 -DCLANG_ABI_COMPAT=6 -// RUN: %clang_cc1 -triple x86_64-unknown-unknown %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -fclang-abi-compat=14 -DCLANG_ABI_COMPAT=14 -// RUN: %clang_cc1 -triple x86_64-unknown-unknown %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -fclang-abi-compat=15 -DCLANG_ABI_COMPAT=15 -// RUN: %clang_cc1 -triple x86_64-unknown-unknown %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -fclang-abi-compat=16 -DCLANG_ABI_COMPAT=16 -// RUN: %clang_cc1 -triple powerpc-ibm-aix7.3.0.0 %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -DCLANG_ABI_COMPAT=15 -// RUN: %clang_cc1 -triple powerpc-ibm-aix7.3.0.0 %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -fclang-abi-compat=15 -DCLANG_ABI_COMPAT=15 -// RUN: %clang_cc1 -triple powerpc64-ibm-aix7.3.0.0 %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -DCLANG_ABI_COMPAT=15 -// RUN: %clang_cc1 -triple powerpc64-ibm-aix7.3.0.0 %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -fclang-abi-compat=15 -DCLANG_ABI_COMPAT=15 -// RUN: %clang_cc1 -triple s390x-none-zos %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -// RUN: %clang_cc1 -triple s390x-none-zos %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -fclang-abi-compat=15 -DCLANG_ABI_COMPAT=15 +// RUN: %clang_cc1 -triple x86_64-unknown-unknown %s -fsyntax-only -verify -std=c++98 -Wno-inaccessible-base -Wno-invalid-offsetof -Wno-c++11-extensions +// RUN: %clang_cc1 -triple x86_64-unknown-unknown %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -Wno-invalid-offsetof +// RUN: %clang_cc1 -triple x86_64-apple-darwin %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -Wno-invalid-offsetof -DCLANG_ABI_COMPAT=15 +// RUN: %clang_cc1 -triple x86_64-scei-ps4 %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -Wno-invalid-offsetof -DCLANG_ABI_COMPAT=6 +// RUN: %clang_cc1 -triple x86_64-sie-ps5 %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -Wno-invalid-offsetof -DCLANG_ABI_COMPAT=6 +// RUN: %clang_cc1 -triple x86_64-unknown-unknown %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -Wno-invalid-offsetof -fclang-abi-compat=6 -DCLANG_ABI_COMPAT=6 +// RUN: %clang_cc1 -triple x86_64-unknown-unknown %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -Wno-invalid-offsetof -fclang-abi-compat=14 -DCLANG_ABI_COMPAT=14 +// RUN: %clang_cc1 -triple x86_64-unknown-unknown %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -Wno-invalid-offsetof -fclang-abi-compat=15 -DCLANG_ABI_COMPAT=15 +// RUN: %clang_cc1 -triple x86_64-unknown-unknown %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -Wno-invalid-offsetof -fclang-abi-compat=16 -DCLANG_ABI_COMPAT=16 +// RUN: %clang_cc1 -triple powerpc-ibm-aix7.3.0.0 %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -Wno-invalid-offsetof -DCLANG_ABI_COMPAT=15 +// RUN: %clang_cc1 -triple powerpc-ibm-aix7.3.0.0 %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -Wno-invalid-offsetof -fclang-abi-compat=15 -DCLANG_ABI_COMPAT=15 +// RUN: %clang_cc1 -triple powerpc64-ibm-aix7.3.0.0 %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -Wno-invalid-offsetof -DCLANG_ABI_COMPAT=15 +// RUN: %clang_cc1 -triple powerpc64-ibm-aix7.3.0.0 %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -Wno-invalid-offsetof -fclang-abi-compat=15 -DCLANG_ABI_COMPAT=15 +// RUN: %clang_cc1 -triple s390x-none-zos %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -Wno-invalid-offsetof +// RUN: %clang_cc1 -triple s390x-none-zos %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base -Wno-invalid-offsetof -fclang-abi-compat=15 -DCLANG_ABI_COMPAT=15 // RUN: %clang_cc1 -fexperimental-new-constant-interpreter -triple x86_64-unknown-unknown %s -fsyntax-only -verify -std=c++98 -Wno-inaccessible-base -Wno-c++11-extensions // RUN: %clang_cc1 -fexperimental-new-constant-interpreter -triple x86_64-unknown-unknown %s -fsyntax-only -verify -std=c++11 -Wno-inaccessible-base diff --git a/clang/test/SemaCXX/ms_struct.cpp b/clang/test/SemaCXX/ms_struct.cpp index e6f0a25b38ea80c..995e424d1f87640 100644 --- a/clang/test/SemaCXX/ms_struct.cpp +++ b/clang/test/SemaCXX/ms_struct.cpp @@ -25,6 +25,7 @@ struct B : public A { static_assert(__builtin_offsetof(B, d) == 12, "We can't allocate the bitfield into the padding under ms_struct"); +// expected-warning@-2 {{offset of on non-standard-layout type 'B'}} struct C { #ifdef TEST_FOR_ERROR @@ -38,6 +39,5 @@ struct C { static_assert(__builtin_offsetof(C, n) == 8, "long long field in ms_struct should be 8-byte aligned"); -#if !defined(TEST_FOR_ERROR) && !defined(TEST_FOR_WARNING) -// expected-no-diagnostics -#endif +// expected-warning@-2 {{offset of on non-standard-layout type 'C'}} + diff --git a/clang/test/SemaCXX/offsetof.cpp b/clang/test/SemaCXX/offsetof.cpp index c984657ebe1f0ed..c4e86369f007dcb 100644 --- a/clang/test/SemaCXX/offsetof.cpp +++ b/clang/test/SemaCXX/offsetof.cpp @@ -51,9 +51,9 @@ struct Derived2 : public Base1, public Base2 { int z; }; -int derived1[__builtin_offsetof(Derived2, x) == 0? 1 : -1]; -int derived2[__builtin_offsetof(Derived2, y) == 4? 1 : -1]; -int derived3[__builtin_offsetof(Derived2, z) == 8? 1 : -1]; +int derived1[__builtin_offsetof(Derived2, x) == 0? 1 : -1]; // expected-warning{{offset of on non-POD type 'Derived2'}} +int derived2[__builtin_offsetof(Derived2, y) == 4? 1 : -1]; // expected-warning{{offset of on non-POD type 'Derived2'}} +int derived3[__builtin_offsetof(Derived2, z) == 8? 1 : -1]; // expected-warning{{offset of on non-POD type 'Derived2'}} // offsetof referring to anonymous struct in base. // PR7769 @@ -66,7 +66,8 @@ struct foo { struct bar : public foo { }; -int anonstruct[__builtin_offsetof(bar, x) == 0 ? 1 : -1]; +int anonstruct[__builtin_offsetof(bar, x) == 0 ? 1 : -1]; // expected-warning{{offset of on non-POD type 'bar'}} + struct LtoRCheck { int a[10]; diff --git a/libcxx/include/__type_traits/datasizeof.h b/libcxx/include/__type_traits/datasizeof.h index 019099a9cf183b5..88a702470c3c15a 100644 --- a/libcxx/include/__type_traits/datasizeof.h +++ b/libcxx/include/__type_traits/datasizeof.h @@ -47,7 +47,11 @@ struct __libcpp_datasizeof { }; #endif + _LIBCPP_DIAGNOSTIC_PUSH + _LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Winvalid-offsetof") + _LIBCPP_GCC_DIAGNOSTIC_IGNORED("-Winvalid-offsetof") static const size_t value = offsetof(_FirstPaddingByte<>, __first_padding_byte_); + _LIBCPP_DIAGNOSTIC_POP }; _LIBCPP_END_NAMESPACE_STD `````````` </details> https://github.com/llvm/llvm-project/pull/65246 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
