Don't emit calls to virtual [[noreturn]] functions as noreturn; overrides of a

[[noreturn]] function are not required to also be [[noreturn]]. We still emit
calls to virtual __attribute__((noreturn)) functions as noreturn; unlike GCC,
we do require overriders to also be noreturn for that attribute.

llvm-svn: 176476

1 files changed, 4 insertions, 1 deletions

diff --git a/clang/lib/CodeGen/CGCall.cpp b/clang/lib/CodeGen/CGCall.cpp
index 4e8e724ea5a..6aabd64f9bd 100644
--- a/clang/lib/CodeGen/CGCall.cpp
+++ b/clang/lib/CodeGen/CGCall.cpp
@@ -993,7 +993,10 @@ void CodeGenModule::ConstructAttributeList(const CGFunctionInfo &FI,
       const FunctionProtoType *FPT = Fn->getType()->getAs<FunctionProtoType>();
       if (FPT && FPT->isNothrow(getContext()))
         FuncAttrs.addAttribute(llvm::Attribute::NoUnwind);
-      if (Fn->isNoReturn())
+      // Don't use [[noreturn]] or _Noreturn for a call to a virtual function.
+      // These attributes are not inherited by overloads.
+      const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Fn);
+      if (Fn->isNoReturn() && !(AttrOnCallSite && MD && MD->isVirtual()))
         FuncAttrs.addAttribute(llvm::Attribute::NoReturn);
     }