llvm-project/clang/test/CodeGen/24-bit.c

// RUN:  %clang_cc1 -triple x86_64-linux-gnu -emit-llvm -O0 -o - %s | FileCheck %s

static union ibtt2
{
  struct ibtt0 { signed ibt0:10; unsigned short ibt1; } ibt5;
  struct ibtt1 { signed ibt2:3; signed ibt3:9; signed ibt4:9; } ibt6;
} ibt15 = {{267, 15266}};

void callee_ibt0f(union ibtt2 ibtp5);

void test(void) {
// CHECK: = load i32, i32*
  callee_ibt0f(ibt15);
}