Author: arphaman Date: Wed Oct 12 04:36:35 2016 New Revision: 283995 URL: http://llvm.org/viewvc/llvm-project?rev=283995&view=rev Log: [Sema] Handle transparent_union attributes in C mode only
This commit marks the transparent_union attributes as C only because clang doesn't support them in C++ mode. Prior to this commit, clang still tried to verify these attributes in C++, leading to crashes when analyzing templated transparent_union unions that have dependent field types. This commit ensures that such crashes won't happen again. As a result of this commit clang now displays a warning every time it encounters a transparent_union attribute in C++ mode. Differential Revision: https://reviews.llvm.org/D25308 Modified: cfe/trunk/include/clang/Basic/Attr.td cfe/trunk/test/SemaCXX/attr-gnu.cpp Modified: cfe/trunk/include/clang/Basic/Attr.td URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/Attr.td?rev=283995&r1=283994&r2=283995&view=diff ============================================================================== --- cfe/trunk/include/clang/Basic/Attr.td (original) +++ cfe/trunk/include/clang/Basic/Attr.td Wed Oct 12 04:36:35 2016 @@ -1543,6 +1543,7 @@ def TransparentUnion : InheritableAttr { let Spellings = [GCC<"transparent_union">]; // let Subjects = SubjectList<[Record, TypedefName]>; let Documentation = [Undocumented]; + let LangOpts = [COnly]; } def Unavailable : InheritableAttr { Modified: cfe/trunk/test/SemaCXX/attr-gnu.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/attr-gnu.cpp?rev=283995&r1=283994&r2=283995&view=diff ============================================================================== --- cfe/trunk/test/SemaCXX/attr-gnu.cpp (original) +++ cfe/trunk/test/SemaCXX/attr-gnu.cpp Wed Oct 12 04:36:35 2016 @@ -27,3 +27,19 @@ public: void test3() __attribute__((cf_unknown_transfer)) override {} // Ok, not known to GCC. }; } + +template<typename T> +union Tu { T b; } __attribute__((transparent_union)); // expected-warning {{'transparent_union' attribute ignored}} + +template<typename T> +union Tu2 { int x; T b; } __attribute__((transparent_union)); // expected-warning {{'transparent_union' attribute ignored}} + +union Tu3 { int x; } __attribute((transparent_union)); // expected-warning {{'transparent_union' attribute ignored}} + +void tuTest1(Tu<int> u); // expected-note {{candidate function not viable: no known conversion from 'int' to 'Tu<int>' for 1st argument}} +void tuTest2(Tu3 u); // expected-note {{candidate function not viable: no known conversion from 'int' to 'Tu3' for 1st argument}} +void tu() { + int x = 2; + tuTest1(x); // expected-error {{no matching function for call to 'tuTest1'}} + tuTest2(x); // expected-error {{no matching function for call to 'tuTest2'}} +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits