[SPEC2006] error: value doesn't match function result type '%x_struct = type { i32, i32 }'

[zqb-all]

spec2k6 462.libquantum build fail.
one of the errors can be reproduce by the following code:

struct x_struct {
  int y;
  int z;
};

typedef struct x_struct x;

x foo(int a)
{
	x m;
	if (a)
		exit(1);
	return m;
}

cmd

xcalcc -c a.c

error:

2023-10-28 15:56:45,554 - xcalcc - ERROR - /open64/bin/../lib/gcc-lib/x86_64-open64-linux/5.0/llc: error: /open64/bin/../lib/gcc-lib/x86_64-open64-linux/5.0/llc: a.O.ll:18:7: error: value doesn't match function result type '%x_struct = type { i32, i32 }'
  ret void
      ^ (xcalcc:630)