Author: gbiv Date: Mon May 8 23:06:24 2017 New Revision: 302506 URL: http://llvm.org/viewvc/llvm-project?rev=302506&view=rev Log: [Sema] Make typeof(OverloadedFunctionName) not a pointer.
We were sometimes doing a function->pointer conversion in Sema::CheckPlaceholderExpr, which isn't the job of CheckPlaceholderExpr. So, when we saw typeof(OverloadedFunctionName), where OverloadedFunctionName referenced a name with only one function that could have its address taken, we'd give back a function pointer type instead of a function type. This is incorrect. I kept the logic for doing the function pointer conversion in resolveAndFixAddressOfOnlyViableOverloadCandidate because it was more consistent with existing ResolveAndFix* methods. Modified: cfe/trunk/include/clang/Sema/Sema.h cfe/trunk/lib/Sema/SemaCast.cpp cfe/trunk/lib/Sema/SemaOverload.cpp cfe/trunk/test/Sema/overloadable.c cfe/trunk/test/SemaCXX/enable_if.cpp Modified: cfe/trunk/include/clang/Sema/Sema.h URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Sema/Sema.h?rev=302506&r1=302505&r2=302506&view=diff ============================================================================== --- cfe/trunk/include/clang/Sema/Sema.h (original) +++ cfe/trunk/include/clang/Sema/Sema.h Mon May 8 23:06:24 2017 @@ -2726,7 +2726,8 @@ public: resolveAddressOfOnlyViableOverloadCandidate(Expr *E, DeclAccessPair &FoundResult); - bool resolveAndFixAddressOfOnlyViableOverloadCandidate(ExprResult &SrcExpr); + bool resolveAndFixAddressOfOnlyViableOverloadCandidate( + ExprResult &SrcExpr, bool DoFunctionPointerConversion = false); FunctionDecl * ResolveSingleFunctionTemplateSpecialization(OverloadExpr *ovl, Modified: cfe/trunk/lib/Sema/SemaCast.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaCast.cpp?rev=302506&r1=302505&r2=302506&view=diff ============================================================================== --- cfe/trunk/lib/Sema/SemaCast.cpp (original) +++ cfe/trunk/lib/Sema/SemaCast.cpp Mon May 8 23:06:24 2017 @@ -1871,7 +1871,8 @@ static bool fixOverloadedReinterpretCast // No guarantees that ResolveAndFixSingleFunctionTemplateSpecialization // preserves Result. Result = E; - if (!Self.resolveAndFixAddressOfOnlyViableOverloadCandidate(Result)) + if (!Self.resolveAndFixAddressOfOnlyViableOverloadCandidate( + Result, /*DoFunctionPointerConversion=*/true)) return false; return Result.isUsable(); } Modified: cfe/trunk/lib/Sema/SemaOverload.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaOverload.cpp?rev=302506&r1=302505&r2=302506&view=diff ============================================================================== --- cfe/trunk/lib/Sema/SemaOverload.cpp (original) +++ cfe/trunk/lib/Sema/SemaOverload.cpp Mon May 8 23:06:24 2017 @@ -11210,12 +11210,12 @@ Sema::resolveAddressOfOnlyViableOverload /// \brief Given an overloaded function, tries to turn it into a non-overloaded /// function reference using resolveAddressOfOnlyViableOverloadCandidate. This /// will perform access checks, diagnose the use of the resultant decl, and, if -/// necessary, perform a function-to-pointer decay. +/// requested, potentially perform a function-to-pointer decay. /// /// Returns false if resolveAddressOfOnlyViableOverloadCandidate fails. /// Otherwise, returns true. This may emit diagnostics and return true. bool Sema::resolveAndFixAddressOfOnlyViableOverloadCandidate( - ExprResult &SrcExpr) { + ExprResult &SrcExpr, bool DoFunctionPointerConverion) { Expr *E = SrcExpr.get(); assert(E->getType() == Context.OverloadTy && "SrcExpr must be an overload"); @@ -11230,7 +11230,7 @@ bool Sema::resolveAndFixAddressOfOnlyVia DiagnoseUseOfDecl(Found, E->getExprLoc()); CheckAddressOfMemberAccess(E, DAP); Expr *Fixed = FixOverloadedFunctionReference(E, DAP, Found); - if (Fixed->getType()->isFunctionType()) + if (DoFunctionPointerConverion && Fixed->getType()->isFunctionType()) SrcExpr = DefaultFunctionArrayConversion(Fixed, /*Diagnose=*/false); else SrcExpr = Fixed; Modified: cfe/trunk/test/Sema/overloadable.c URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Sema/overloadable.c?rev=302506&r1=302505&r2=302506&view=diff ============================================================================== --- cfe/trunk/test/Sema/overloadable.c (original) +++ cfe/trunk/test/Sema/overloadable.c Mon May 8 23:06:24 2017 @@ -151,3 +151,18 @@ void dropping_qualifiers_is_incompatible foo(ccharbuf); // expected-error{{call to 'foo' is ambiguous}} expected-note@148{{candidate function}} expected-note@149{{candidate function}} foo(vcharbuf); // expected-error{{call to 'foo' is ambiguous}} expected-note@148{{candidate function}} expected-note@149{{candidate function}} } + +// Bug: we used to treat `__typeof__(foo)` as though it was `__typeof__(&foo)` +// if `foo` was overloaded with only one function that could have its address +// taken. +void typeof_function_is_not_a_pointer() { + void not_a_pointer(void *) __attribute__((overloadable)); + void not_a_pointer(char *__attribute__((pass_object_size(1)))) + __attribute__((overloadable)); + + __typeof__(not_a_pointer) *fn; + + void take_fn(void (*)(void *)); + // if take_fn is passed a void (**)(void *), we'll get a warning. + take_fn(fn); +} Modified: cfe/trunk/test/SemaCXX/enable_if.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/enable_if.cpp?rev=302506&r1=302505&r2=302506&view=diff ============================================================================== --- cfe/trunk/test/SemaCXX/enable_if.cpp (original) +++ cfe/trunk/test/SemaCXX/enable_if.cpp Mon May 8 23:06:24 2017 @@ -499,3 +499,17 @@ void run() { } } } + +namespace TypeOfFn { + template <typename T, typename U> + struct is_same; + + template <typename T> struct is_same<T, T> { + enum { value = 1 }; + }; + + void foo(int a) __attribute__((enable_if(a, ""))); + void foo(float a) __attribute__((enable_if(1, ""))); + + static_assert(is_same<__typeof__(foo)*, decltype(&foo)>::value, ""); +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits