[Clang] Fix crash on void{} (#147514)

Caused by an incorrect assertion.

Fixes #116440

Author: cor3ntin

clang/lib/CodeGen/CGExprScalar.cpp

@@ -2114,8 +2114,10 @@ static int getAsInt32(llvm::ConstantInt *C, llvm::Type *I32Ty) {
 Value *ScalarExprEmitter::VisitInitListExpr(InitListExpr *E) {
   bool Ignore = TestAndClearIgnoreResultAssign();
   (void)Ignore;
-  assert (Ignore == false && "init list ignored");
   unsigned NumInitElements = E->getNumInits();
+  assert(Ignore == false ||
+         (NumInitElements == 0 && E->getType()->isVoidType()) &&
+             "init list ignored");
 
   // HLSL initialization lists in the AST are an expansion which can contain
   // side-effecting expressions wrapped in opaque value expressions. To properly

clang/test/CodeGenCXX/cxx0x-initializer-scalars.cpp

@@ -1,7 +1,19 @@
-// RUN: %clang_cc1 -std=c++11 -emit-llvm -o - %s | FileCheck %s
+// RUN: %clang_cc1 -std=c++11 -triple x86_64-linux -emit-llvm -o - %s | FileCheck %s
 
 void f()
 {
   // CHECK: store i32 0
   int i{};
 }
+
+
+namespace GH116440 {
+void f() {
+  void{};
+  void();
+}
+
+// CHECK: define{{.*}} void @_ZN8GH1164401fEv()
+// CHECK-NEXT: entry
+// CHECK-NEXT: ret void
+}