From dab73ce1dc5b0398b906d828e06afadae14d3c8f Mon Sep 17 00:00:00 2001 From: Richard Smith Date: Wed, 28 Nov 2018 06:25:06 +0000 Subject: [PATCH] PR39809: (const void*)0 is not a null pointer constant in C. llvm-svn: 347730 --- clang/lib/AST/Expr.cpp | 12 ++++++------ clang/test/Sema/conditional.c | 7 +++++++ 2 files changed, 13 insertions(+), 6 deletions(-) diff --git a/clang/lib/AST/Expr.cpp b/clang/lib/AST/Expr.cpp index ec6f084aedf6..d8df83def4b9 100644 --- a/clang/lib/AST/Expr.cpp +++ b/clang/lib/AST/Expr.cpp @@ -3441,20 +3441,20 @@ Expr::isNullPointerConstant(ASTContext &Ctx, // Check that it is a cast to void*. if (const PointerType *PT = CE->getType()->getAs()) { QualType Pointee = PT->getPointeeType(); + Qualifiers Qs = Pointee.getQualifiers(); // Only (void*)0 or equivalent are treated as nullptr. If pointee type // has non-default address space it is not treated as nullptr. // (__generic void*)0 in OpenCL 2.0 should not be treated as nullptr // since it cannot be assigned to a pointer to constant address space. - bool PointeeHasDefaultAS = - Pointee.getAddressSpace() == LangAS::Default || - (Ctx.getLangOpts().OpenCLVersion >= 200 && + if ((Ctx.getLangOpts().OpenCLVersion >= 200 && Pointee.getAddressSpace() == LangAS::opencl_generic) || (Ctx.getLangOpts().OpenCL && Ctx.getLangOpts().OpenCLVersion < 200 && - Pointee.getAddressSpace() == LangAS::opencl_private); + Pointee.getAddressSpace() == LangAS::opencl_private)) + Qs.removeAddressSpace(); - if (PointeeHasDefaultAS && Pointee->isVoidType() && // to void* - CE->getSubExpr()->getType()->isIntegerType()) // from int. + if (Pointee->isVoidType() && Qs.empty() && // to void* + CE->getSubExpr()->getType()->isIntegerType()) // from int return CE->getSubExpr()->isNullPointerConstant(Ctx, NPC); } } diff --git a/clang/test/Sema/conditional.c b/clang/test/Sema/conditional.c index 3d7bccaf9758..1f3a6d04f14d 100644 --- a/clang/test/Sema/conditional.c +++ b/clang/test/Sema/conditional.c @@ -12,3 +12,10 @@ int _php_stream_free1() { int _php_stream_free2() { return (1 ? _efree(0) : free(0)); // expected-error {{returning 'void' from a function with incompatible result type 'int'}} } + +void pr39809() { + _Generic(0 ? (int const *)0 : (void *)0, int const *: (void)0); + _Generic(0 ? (int const *)0 : (void *)1, void const *: (void)0); + _Generic(0 ? (int volatile*)0 : (void const*)1, void volatile const*: (void)0); + _Generic(0 ? (int volatile*)0 : (void const*)0, void volatile const*: (void)0); +}