Author: Max Winkler Date: 2024-08-15T18:02:08-07:00 New Revision: 9088ac1e8335d32bed275fbd33f0cd1b9bd400d6
URL: https://github.com/llvm/llvm-project/commit/9088ac1e8335d32bed275fbd33f0cd1b9bd400d6 DIFF: https://github.com/llvm/llvm-project/commit/9088ac1e8335d32bed275fbd33f0cd1b9bd400d6.diff LOG: [Clang] [Sema] Error on reference types inside a union with msvc 1900+ (#102851) Godbolt for reference: https://godbolt.org/z/ovKjvWc46 I can confirm that this extension is no longer valid in VS2017, VS2019 and VS2022 under `/permissive` and `/permissive-` MSDN, https://learn.microsoft.com/en-us/cpp/porting/visual-cpp-what-s-new-2003-through-2015?view=msvc-170, says this extension was officially removed in VS2015. Added: Modified: clang/docs/ReleaseNotes.rst clang/lib/Sema/SemaDecl.cpp clang/test/SemaCXX/MicrosoftExtensions.cpp Removed: ################################################################################ diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index 598fccfe59bff1..ffdd063ec99037 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -321,6 +321,12 @@ Android Support Windows Support ^^^^^^^^^^^^^^^ +- Clang no longer allows references inside a union when emulating MSVC 1900+ even if `fms-extensions` is enabled. + Starting with VS2015, MSVC 1900, this Microsoft extension is no longer allowed and always results in an error. + Clang now follows the MSVC behavior in this scenario. + When `-fms-compatibility-version=18.00` or prior is set on the command line this Microsoft extension is still + allowed as VS2013 and prior allow it. + LoongArch Support ^^^^^^^^^^^^^^^^^ diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp index 83a652691e2e03..d19a16cf2ba150 100644 --- a/clang/lib/Sema/SemaDecl.cpp +++ b/clang/lib/Sema/SemaDecl.cpp @@ -18507,11 +18507,15 @@ FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, // the program is ill-formed, except when compiling with MSVC extensions // enabled. if (EltTy->isReferenceType()) { - Diag(NewFD->getLocation(), getLangOpts().MicrosoftExt ? - diag::ext_union_member_of_reference_type : - diag::err_union_member_of_reference_type) - << NewFD->getDeclName() << EltTy; - if (!getLangOpts().MicrosoftExt) + const bool HaveMSExt = + getLangOpts().MicrosoftExt && + !getLangOpts().isCompatibleWithMSVC(LangOptions::MSVC2015); + + Diag(NewFD->getLocation(), + HaveMSExt ? diag::ext_union_member_of_reference_type + : diag::err_union_member_of_reference_type) + << NewFD->getDeclName() << EltTy; + if (!HaveMSExt) NewFD->setInvalidDecl(); } } diff --git a/clang/test/SemaCXX/MicrosoftExtensions.cpp b/clang/test/SemaCXX/MicrosoftExtensions.cpp index 98c19975095bbe..7454a01158f6b4 100644 --- a/clang/test/SemaCXX/MicrosoftExtensions.cpp +++ b/clang/test/SemaCXX/MicrosoftExtensions.cpp @@ -1,8 +1,10 @@ -// RUN: %clang_cc1 -std=c++17 %s -triple i686-pc-win32 -fsyntax-only -Wmicrosoft -Wc++11-extensions -Wno-long-long -verify -fms-extensions -fexceptions -fcxx-exceptions -DTEST1 -// RUN: %clang_cc1 -std=c++98 %s -triple i686-pc-win32 -fsyntax-only -Wmicrosoft -Wc++11-extensions -Wno-long-long -verify=expected,precxx17 -fms-extensions -fexceptions -fcxx-exceptions -DTEST1 -// RUN: %clang_cc1 -std=c++11 %s -triple i686-pc-win32 -fsyntax-only -Wmicrosoft -Wc++11-extensions -Wno-long-long -verify=expected,precxx17 -fms-extensions -fexceptions -fcxx-exceptions -DTEST1 -// RUN: %clang_cc1 -std=c++14 %s -triple i686-pc-win32 -fsyntax-only -Wmicrosoft -Wc++11-extensions -Wno-long-long -verify=expected,precxx17 -fexceptions -fcxx-exceptions -DTEST2 -// RUN: %clang_cc1 %s -triple i686-pc-win32 -fsyntax-only -std=c++11 -fms-compatibility -verify -DTEST3 +// RUN: %clang_cc1 -std=c++17 %s -triple i686-pc-win32 -fsyntax-only -Wmicrosoft -Wc++11-extensions -Wno-long-long -verify=expected,ms-union-ext -fms-extensions -fexceptions -fcxx-exceptions -DTEST1 +// RUN: %clang_cc1 -std=c++98 %s -triple i686-pc-win32 -fsyntax-only -Wmicrosoft -Wc++11-extensions -Wno-long-long -verify=expected,precxx17,ms-union-ext -fms-extensions -fexceptions -fcxx-exceptions -DTEST1 +// RUN: %clang_cc1 -std=c++11 %s -triple i686-pc-win32 -fsyntax-only -Wmicrosoft -Wc++11-extensions -Wno-long-long -verify=expected,precxx17,ms-union-ext -fms-extensions -fexceptions -fcxx-exceptions -DTEST1 +// RUN: %clang_cc1 -std=c++14 %s -triple i686-pc-win32 -fsyntax-only -Wmicrosoft -Wc++11-extensions -Wno-long-long -verify=expected,precxx17,ms-union-ext-disabled -fexceptions -fcxx-exceptions -DTEST2 +// RUN: %clang_cc1 %s -triple i686-pc-win32 -fsyntax-only -std=c++11 -fms-compatibility -verify=expected,ms-union-ext -DTEST3 +// RUN: %clang_cc1 -std=c++17 %s -triple i686-pc-win32 -fsyntax-only -Wmicrosoft -verify=ms-union-ext -fms-extensions -fms-compatibility-version=18.00 +// RUN: %clang_cc1 -std=c++17 %s -triple i686-pc-win32 -fsyntax-only -Wmicrosoft -verify=ms-union-ext-disabled -fms-extensions -fms-compatibility-version=19.00 #if TEST1 @@ -384,11 +386,6 @@ void TestSP9() { c3.h(); // Overloaded unary op operand } -union u { - int *i1; - int &i2; // expected-warning {{union member 'i2' has reference type 'int &', which is a Microsoft extension}} -}; - // Property getter using reference. struct SP11 { __declspec(property(get=GetV)) int V; @@ -619,9 +616,12 @@ template<typename T> struct A {}; template<typename T> struct B : A<A<T>> { A<T>::C::D d; }; // expected-warning {{implicit 'typename' is a C++20 extension}} } -#else - -#error Unknown test mode - #endif +union u { + int *i1; + + // ms-union-ext-warning@+2 {{union member 'i2' has reference type 'int &', which is a Microsoft extension}} + // ms-union-ext-disabled-error@+1 {{union member 'i2' has reference type 'int &'}} + int &i2; +}; _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
