From 92b43a462e141fac169a162616f464000633cece Mon Sep 17 00:00:00 2001 From: George Burgess IV Date: Thu, 21 Jul 2016 03:28:13 +0000 Subject: [PATCH] [Sema] Fix PR28623. In atomic builtins, we assumed that the LValue conversion on the first argument would succeed. So, we would crash given code like: ``` void ovl(char); void ovl(int); __atomic_store_n(ovl, 0, 0); ``` This patch makes us not assume that said conversion is successful. :) llvm-svn: 276232 --- clang/lib/Sema/SemaChecking.cpp | 6 +++++- clang/test/SemaCXX/atomic-ops.cpp | 9 +++++++++ 2 files changed, 14 insertions(+), 1 deletion(-) create mode 100644 clang/test/SemaCXX/atomic-ops.cpp diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp index 7a99fc838302..6a4f65adb885 100644 --- a/clang/lib/Sema/SemaChecking.cpp +++ b/clang/lib/Sema/SemaChecking.cpp @@ -2398,7 +2398,11 @@ ExprResult Sema::SemaAtomicOpsOverloaded(ExprResult TheCallResult, // Inspect the first argument of the atomic operation. Expr *Ptr = TheCall->getArg(0); - Ptr = DefaultFunctionArrayLvalueConversion(Ptr).get(); + ExprResult ConvertedPtr = DefaultFunctionArrayLvalueConversion(Ptr); + if (ConvertedPtr.isInvalid()) + return ExprError(); + + Ptr = ConvertedPtr.get(); const PointerType *pointerType = Ptr->getType()->getAs(); if (!pointerType) { Diag(DRE->getLocStart(), diag::err_atomic_builtin_must_be_pointer) diff --git a/clang/test/SemaCXX/atomic-ops.cpp b/clang/test/SemaCXX/atomic-ops.cpp new file mode 100644 index 000000000000..213161364f58 --- /dev/null +++ b/clang/test/SemaCXX/atomic-ops.cpp @@ -0,0 +1,9 @@ +// RUN: %clang_cc1 %s -verify -fsyntax-only -triple=i686-linux-gnu -std=c++11 + +// We crashed when we couldn't properly convert the first arg of __atomic_* to +// an lvalue. +void PR28623() { + void helper(int); // expected-note{{target}} + void helper(char); // expected-note{{target}} + __atomic_store_n(helper, 0, 0); // expected-error{{reference to overloaded function could not be resolved}} +}