llvm-project/clang/test/CodeGen/funccall.c

static int q;

void foo() {
  int t = q;
  q = t + 1;
}
int main() {
  q = 0;
  foo();
  q = q - 1;

  return q;
}

// This is the source that corresponds to funccall.ll
// RUN: echo foo