Author: arphaman Date: Thu Mar 30 08:48:33 2017 New Revision: 299080 URL: http://llvm.org/viewvc/llvm-project?rev=299080&view=rev Log: [ARC][ObjC++] Use ObjC semantic rules for comparisons between a pointer and an ObjC object pointer
When ARC is enabled in Objective-C++, comparisons between a pointer and Objective-C object pointer typically result in errors like this: "invalid operands to a binary expression". This error message can be quite confusing as it doesn't provide a solution to the problem, unlike the non-C++ diagnostic: "implicit conversion of Objective-C pointer type 'id' to C pointer type 'void *' requires a bridged cast" (it also provides fix-its). This commit forces comparisons between pointers and Objective-C object pointers in ARC to use the Objective-C semantic rules to ensure that a better diagnostic is reported. rdar://31103857 Differential Revision: https://reviews.llvm.org/D31177 Added: cfe/trunk/test/SemaObjCXX/arc-ptr-comparison.mm Modified: cfe/trunk/lib/Sema/SemaExpr.cpp Modified: cfe/trunk/lib/Sema/SemaExpr.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaExpr.cpp?rev=299080&r1=299079&r2=299080&view=diff ============================================================================== --- cfe/trunk/lib/Sema/SemaExpr.cpp (original) +++ cfe/trunk/lib/Sema/SemaExpr.cpp Thu Mar 30 08:48:33 2017 @@ -9423,7 +9423,10 @@ QualType Sema::CheckCompareOperands(Expr // If both operands are pointers, [...] bring them to their composite // pointer type. if ((int)LHSType->isPointerType() + (int)RHSType->isPointerType() >= - (IsRelational ? 2 : 1)) { + (IsRelational ? 2 : 1) && + (!LangOpts.ObjCAutoRefCount || + !(LHSType->isObjCObjectPointerType() || + RHSType->isObjCObjectPointerType()))) { if (convertPointersToCompositeType(*this, Loc, LHS, RHS)) return QualType(); else Added: cfe/trunk/test/SemaObjCXX/arc-ptr-comparison.mm URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaObjCXX/arc-ptr-comparison.mm?rev=299080&view=auto ============================================================================== --- cfe/trunk/test/SemaObjCXX/arc-ptr-comparison.mm (added) +++ cfe/trunk/test/SemaObjCXX/arc-ptr-comparison.mm Thu Mar 30 08:48:33 2017 @@ -0,0 +1,24 @@ +// RUN: %clang_cc1 -std=c++11 -triple x86_64-apple-darwin11 -fsyntax-only -fobjc-arc -verify %s +// RUN: %clang_cc1 -std=c++11 -triple x86_64-apple-darwin11 -fsyntax-only -verify -DNOARC %s +#ifdef NOARC +// expected-no-diagnostics +#endif + +int testObjCComparisonRules(void *v, id x, id y) { + return v == x; +#ifndef NOARC +// expected-error@-2 {{implicit conversion of Objective-C pointer type 'id' to C pointer type 'void *' requires a bridged cast}} +// expected-note@-3 {{use __bridge to convert directly (no change in ownership)}} +// expected-note@-4 {{use __bridge_retained to make an ARC object available as a +1 'void *'}} +#endif + return v >= x; +#ifndef NOARC +// expected-error@-2 {{implicit conversion of Objective-C pointer type 'id' to C pointer type 'void *' requires a bridged cast}} +// expected-note@-3 {{use __bridge to convert directly (no change in ownership)}} +// expected-note@-4 {{use __bridge_retained to make an ARC object available as a +1 'void *'}} +#endif + return v == (id)(void *)0; // OK + return v == nullptr; // OK + return v == (void *)0; + return x == y; +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
