Author: Aaron Ballman Date: 2020-04-16T09:28:49-04:00 New Revision: 2ec5520a54ef9b359c6154adf857ba690bc117f1
URL: https://github.com/llvm/llvm-project/commit/2ec5520a54ef9b359c6154adf857ba690bc117f1 DIFF: https://github.com/llvm/llvm-project/commit/2ec5520a54ef9b359c6154adf857ba690bc117f1.diff LOG: Disallow [[nodiscard]] on a function pointer declaration. This is not allowed by [dcl.attr.nodiscard]p1 for the standard attribute, but is still supported for the [[clang::warn_unused_result]] spelling. Added: Modified: clang/lib/Sema/SemaDeclAttr.cpp clang/test/CXX/dcl.dcl/dcl.attr/dcl.attr.nodiscard/p2.cpp clang/test/SemaCXX/warn-unused-result.cpp Removed: ################################################################################ diff --git a/clang/lib/Sema/SemaDeclAttr.cpp b/clang/lib/Sema/SemaDeclAttr.cpp index 1a8a73660cf4..3205b4472db2 100644 --- a/clang/lib/Sema/SemaDeclAttr.cpp +++ b/clang/lib/Sema/SemaDeclAttr.cpp @@ -2826,6 +2826,12 @@ static void handleWarnUnusedResult(Sema &S, Decl *D, const ParsedAttr &AL) { StringRef Str; if ((AL.isCXX11Attribute() || AL.isC2xAttribute()) && !AL.getScopeName()) { + // The standard attribute cannot be applied to variable declarations such + // as a function pointer. + if (isa<VarDecl>(D)) + S.Diag(AL.getLoc(), diag::warn_attribute_wrong_decl_type_str) + << AL << "functions, classes, or enumerations"; + // If this is spelled as the standard C++17 attribute, but not in C++17, // warn about using it as an extension. If there are attribute arguments, // then claim it's a C++2a extension instead. diff --git a/clang/test/CXX/dcl.dcl/dcl.attr/dcl.attr.nodiscard/p2.cpp b/clang/test/CXX/dcl.dcl/dcl.attr/dcl.attr.nodiscard/p2.cpp index 3d3223cda756..e2397c12e2e9 100644 --- a/clang/test/CXX/dcl.dcl/dcl.attr/dcl.attr.nodiscard/p2.cpp +++ b/clang/test/CXX/dcl.dcl/dcl.attr/dcl.attr.nodiscard/p2.cpp @@ -26,7 +26,7 @@ void f() { (void)get_e(); } -[[nodiscard]] volatile char &(*fp)(); +[[nodiscard]] volatile char &(*fp)(); // expected-warning {{'nodiscard' attribute only applies to functions, classes, or enumerations}} void g() { fp(); // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}} diff --git a/clang/test/SemaCXX/warn-unused-result.cpp b/clang/test/SemaCXX/warn-unused-result.cpp index f1de4618a741..d0bb4c9317dd 100644 --- a/clang/test/SemaCXX/warn-unused-result.cpp +++ b/clang/test/SemaCXX/warn-unused-result.cpp @@ -246,3 +246,11 @@ void g() { f(b); // expected-warning {{ignoring return value}} } } // namespace PR39837 + +namespace PR45520 { +[[nodiscard]] bool (*f)(); // expected-warning {{'nodiscard' attribute only applies to functions, classes, or enumerations}} +[[clang::warn_unused_result]] bool (*g)(); +__attribute__((warn_unused_result)) bool (*h)(); + +void i([[nodiscard]] bool (*fp)()); // expected-warning {{'nodiscard' attribute only applies to functions, classes, or enumerations}} +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
