Author: epilk Date: Fri Jan 18 13:33:23 2019 New Revision: 351595 URL: http://llvm.org/viewvc/llvm-project?rev=351595&view=rev Log: [Sema] Suppress a warning about a forward-declared fixed enum in C mode
As of r343360, we support fixed-enums in C. This lead to some warnings in project headers where a fixed enum is forward declared then later defined. In C++, this is fine, the forward declaration is treated as a complete type even though the definition isn't present. We use this rule in C too, but still warn about the forward declaration anyways. This patch suppresses the warning. rdar://problem/47356469 Differential revision: https://reviews.llvm.org/D56879 Modified: cfe/trunk/lib/Sema/SemaDecl.cpp cfe/trunk/test/Sema/fixed-enum.c Modified: cfe/trunk/lib/Sema/SemaDecl.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaDecl.cpp?rev=351595&r1=351594&r2=351595&view=diff ============================================================================== --- cfe/trunk/lib/Sema/SemaDecl.cpp (original) +++ cfe/trunk/lib/Sema/SemaDecl.cpp Fri Jan 18 13:33:23 2019 @@ -14747,8 +14747,7 @@ CreateNewDecl: // If this is an undefined enum, warn. if (TUK != TUK_Definition && !Invalid) { TagDecl *Def; - if (IsFixed && (getLangOpts().CPlusPlus11 || getLangOpts().ObjC) && - cast<EnumDecl>(New)->isFixed()) { + if (IsFixed && cast<EnumDecl>(New)->isFixed()) { // C++0x: 7.2p2: opaque-enum-declaration. // Conflicts are diagnosed above. Do nothing. } Modified: cfe/trunk/test/Sema/fixed-enum.c URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Sema/fixed-enum.c?rev=351595&r1=351594&r2=351595&view=diff ============================================================================== --- cfe/trunk/test/Sema/fixed-enum.c (original) +++ cfe/trunk/test/Sema/fixed-enum.c Fri Jan 18 13:33:23 2019 @@ -2,6 +2,7 @@ // RUN: %clang_cc1 -Weverything -xc++ -std=c++03 -DCXX03 -verify %s // RUN: %clang_cc1 -Weverything -xobjective-c -DOBJC -verify %s // RUN: %clang_cc1 -Weverything -std=c11 -xc -DC11 -verify %s +// RUN: %clang_cc1 -pedantic -std=c11 -xc -DC11 -verify %s // RUN: %clang_cc1 -Weverything -std=c11 -xc -fms-extensions -DMS -verify %s enum X : int {e}; @@ -10,9 +11,29 @@ enum X : int {e}; #elif defined(CXX03) // expected-warning@-4{{enumeration types with a fixed underlying type are a C++11 extension}} #elif defined(OBJC) -// expected-no-diagnostics +// No diagnostic #elif defined(C11) // expected-warning@-8{{enumeration types with a fixed underlying type are a Clang extension}} #elif defined(MS) // expected-warning@-10{{enumeration types with a fixed underlying type are a Microsoft extension}} #endif + +// Don't warn about the forward declaration in any language mode. +enum Fwd : int; +enum Fwd : int { e2 }; +#ifndef OBJC +// expected-warning@-3 {{enumeration types with a fixed underlying type}} +// expected-warning@-3 {{enumeration types with a fixed underlying type}} +#endif + +// Always error on the incompatible redeclaration. +enum BadFwd : int; +#ifndef OBJC +// expected-warning@-2 {{enumeration types with a fixed underlying type}} +#endif +// expected-note@-4 {{previous declaration is here}} +enum BadFwd : char { e3 }; +#ifndef OBJC +// expected-warning@-2 {{enumeration types with a fixed underlying type}} +#endif +// expected-error@-4 {{enumeration redeclared with different underlying type 'char' (was 'int')}} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits