There may be ABI compatibility issues prior to commit b29f052.

[the-die]

System V ABI 3.5.7 When a function taking variable-arguments is called, %al must be set to the total number of floating point parameters passed to the function in vector registers.
So variable argument tests with floating-point parameters may fail on some platforms.
Before commit b29f052 changing code

if (depth % 2 == 0) {
  println("  call *%%rax");
} else {
  println("  sub $8, %%rsp");
  println("  call *%%rax");
  println("  add $8, %%rsp");
}

to code

if (depth % 2 == 0) {
  println("  mov %%rax, %%r10");
  println("  mov $%d, %%rax", fp);
  println("  call *%%r10");
} else {
  println("  sub $8, %%rsp");
  println("  mov %%rax, %%r10");
  println("  mov $%d, %%rax", fp);
  println("  call *%%r10");
  println("  add $8, %%rsp");
}

can fix this issue.