llvm-project/clang/test/CodeGen/union-init2.c

// RUN: %clang_cc1 -emit-llvm %s -o - -triple i686-pc-linux-gnu | FileCheck %s

// Make sure we generate something sane instead of a ptrtoint
// CHECK: bitcast (%0* @r to %union.x*), [4 x i8] undef
union x {long long b;union x* a;} r = {.a = &r};


// CHECK: global %1 { [3 x i8] zeroinitializer, [5 x i8] undef }
union z {
  char a[3];
  long long b;
};
union z y = {};