int main(int argc, const char **argv) {
  signed short res;
  if (__builtin_sub_overflow((signed short)0x0, (signed short)0x0, &res)) {
    return -1;
  }
  if (__builtin_sub_overflow((signed short)0x0, (signed short)0x7FFF, &res)) {
    return -1;
  }
  if (!__builtin_sub_overflow((signed short)0x0, (signed short)0x8000, &res)) {
    return -1;
  }
  if (__builtin_sub_overflow((signed short)0x0, (signed short)0x8001, &res)) {
    return -1;
  }
  if (__builtin_sub_overflow((signed short)0x1, (signed short)0x7FFF, &res)) {
    return -1;
  }
  if (__builtin_sub_overflow((signed short)0x7FFF, (signed short)0x0, &res)) {
    return -1;
  }
  if (__builtin_sub_overflow((signed short)0x7FFF, (signed short)0x1, &res)) {
    return -1;
  }
  if (__builtin_sub_overflow((signed short)0x7FFF, (signed short)0x7FFF,
                             &res)) {
    return -1;
  }
  if (!__builtin_sub_overflow((signed short)0x7FFF, (signed short)0x8000,
                              &res)) {
    return -1;
  }
  if (!__builtin_sub_overflow((signed short)0x7FFF, (signed short)0xFFFF,
                              &res)) {
    return -1;
  }
  if (!__builtin_sub_overflow((signed short)0x8000, (signed short)0x7FFF,
                              &res)) {
    return -1;
  }
  if (__builtin_sub_overflow((signed short)0x8000, (signed short)0x8000,
                             &res)) {
    return -1;
  }
  if (__builtin_sub_overflow((signed short)0x8001, (signed short)0x1, &res)) {
    return -1;
  }
  if (!__builtin_sub_overflow((signed short)0x8001, (signed short)0x2, &res)) {
    return -1;
  }
  return 0;
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
movl   $0x0,-0x4(%rbp)
mov    %edi,-0x8(%rbp)
mov    %rsi,-0x10(%rbp)
xor    %eax,%eax
mov    %ax,%cx
sub    $0x0,%cx
seto   %al
mov    %cx,-0x12(%rbp)
test   $0x1,%al
jne    112f <main+0x2f>
jmp    113b <main+0x3b>
movl   $0xffffffff,-0x4(%rbp)
jmp    133b <main+0x23b>
xor    %eax,%eax
mov    %ax,%cx
sub    $0x7fff,%cx
seto   %al
mov    %cx,-0x12(%rbp)
test   $0x1,%al
jne    1159 <main+0x59>
jmp    1165 <main+0x65>
movl   $0xffffffff,-0x4(%rbp)
jmp    133b <main+0x23b>
xor    %eax,%eax
mov    %ax,%cx
sub    $0x8000,%cx
seto   %al
mov    %cx,-0x12(%rbp)
test   $0x1,%al
jne    118a <main+0x8a>
movl   $0xffffffff,-0x4(%rbp)
jmp    133b <main+0x23b>
xor    %eax,%eax
mov    %ax,%cx
sub    $0x8001,%cx
seto   %al
mov    %cx,-0x12(%rbp)
test   $0x1,%al
jne    11a8 <main+0xa8>
jmp    11b4 <main+0xb4>
movl   $0xffffffff,-0x4(%rbp)
jmp    133b <main+0x23b>
mov    $0x1,%cx
sub    $0x7fff,%cx
seto   %al
mov    %cx,-0x12(%rbp)
test   $0x1,%al
jne    11d1 <main+0xd1>
jmp    11dd <main+0xdd>
movl   $0xffffffff,-0x4(%rbp)
jmp    133b <main+0x23b>
mov    $0x7fff,%cx
sub    $0x0,%cx
seto   %al
mov    %cx,-0x12(%rbp)
test   $0x1,%al
jne    11f9 <main+0xf9>
jmp    1205 <main+0x105>
movl   $0xffffffff,-0x4(%rbp)
jmp    133b <main+0x23b>
mov    $0x7fff,%cx
dec    %cx
seto   %al
mov    %cx,-0x12(%rbp)
test   $0x1,%al
jne    1220 <main+0x120>
jmp    122c <main+0x12c>
movl   $0xffffffff,-0x4(%rbp)
jmp    133b <main+0x23b>
mov    $0x7fff,%cx
sub    $0x7fff,%cx
seto   %al
mov    %cx,-0x12(%rbp)
test   $0x1,%al
jne    1249 <main+0x149>
jmp    1255 <main+0x155>
movl   $0xffffffff,-0x4(%rbp)
jmp    133b <main+0x23b>
mov    $0x7fff,%cx
sub    $0x8000,%cx
seto   %al
mov    %cx,-0x12(%rbp)
test   $0x1,%al
jne    1279 <main+0x179>
movl   $0xffffffff,-0x4(%rbp)
jmp    133b <main+0x23b>
mov    $0x7fff,%cx
sub    $0xffff,%cx
seto   %al
mov    %cx,-0x12(%rbp)
test   $0x1,%al
jne    129d <main+0x19d>
movl   $0xffffffff,-0x4(%rbp)
jmp    133b <main+0x23b>
mov    $0x8000,%cx
sub    $0x7fff,%cx
seto   %al
mov    %cx,-0x12(%rbp)
test   $0x1,%al
jne    12c1 <main+0x1c1>
movl   $0xffffffff,-0x4(%rbp)
jmp    133b <main+0x23b>
mov    $0x8000,%cx
sub    $0x8000,%cx
seto   %al
mov    %cx,-0x12(%rbp)
test   $0x1,%al
jne    12de <main+0x1de>
jmp    12ea <main+0x1ea>
movl   $0xffffffff,-0x4(%rbp)
jmp    133b <main+0x23b>
mov    $0x8001,%cx
dec    %cx
seto   %al
mov    %cx,-0x12(%rbp)
test   $0x1,%al
jne    1305 <main+0x205>
jmp    1311 <main+0x211>
movl   $0xffffffff,-0x4(%rbp)
jmp    133b <main+0x23b>
mov    $0x8001,%cx
sub    $0x2,%cx
seto   %al
mov    %cx,-0x12(%rbp)
test   $0x1,%al
jne    1334 <main+0x234>
movl   $0xffffffff,-0x4(%rbp)
jmp    133b <main+0x23b>
movl   $0x0,-0x4(%rbp)
mov    -0x4(%rbp),%eax
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
xor    %eax,%eax
ret

LLVM IR (-O0):
define i32 @main(i32 %0, i8** %1) {
%3 = alloca i32
%4 = alloca i32
%5 = alloca i8**
%6 = alloca i16
store i32 0, i32* %3
store i32 %0, i32* %4
store i8** %1, i8*** %5
%7 = call { i16, i1 } @llvm.ssub.with.overflow.i16(i16 0, i16 0)
%8 = extractvalue { i16, i1 } %7, 1
%9 = extractvalue { i16, i1 } %7, 0
store i16 %9, i16* %6
br i1 %8, label %10, label %11
10: ; preds = %2
store i32 -1, i32* %3
br label %77
11: ; preds = %2
%12 = call { i16, i1 } @llvm.ssub.with.overflow.i16(i16 0, i16 32767)
%13 = extractvalue { i16, i1 } %12, 1
%14 = extractvalue { i16, i1 } %12, 0
store i16 %14, i16* %6
br i1 %13, label %15, label %16
15: ; preds = %11
store i32 -1, i32* %3
br label %77
16: ; preds = %11
%17 = call { i16, i1 } @llvm.ssub.with.overflow.i16(i16 0, i16 -32768)
%18 = extractvalue { i16, i1 } %17, 1
%19 = extractvalue { i16, i1 } %17, 0
store i16 %19, i16* %6
br i1 %18, label %21, label %20
20: ; preds = %16
store i32 -1, i32* %3
br label %77
21: ; preds = %16
%22 = call { i16, i1 } @llvm.ssub.with.overflow.i16(i16 0, i16 -32767)
%23 = extractvalue { i16, i1 } %22, 1
%24 = extractvalue { i16, i1 } %22, 0
store i16 %24, i16* %6
br i1 %23, label %25, label %26
25: ; preds = %21
store i32 -1, i32* %3
br label %77
26: ; preds = %21
%27 = call { i16, i1 } @llvm.ssub.with.overflow.i16(i16 1, i16 32767)
%28 = extractvalue { i16, i1 } %27, 1
%29 = extractvalue { i16, i1 } %27, 0
store i16 %29, i16* %6
br i1 %28, label %30, label %31
30: ; preds = %26
store i32 -1, i32* %3
br label %77
31: ; preds = %26
%32 = call { i16, i1 } @llvm.ssub.with.overflow.i16(i16 32767, i16 0)
%33 = extractvalue { i16, i1 } %32, 1
%34 = extractvalue { i16, i1 } %32, 0
store i16 %34, i16* %6
br i1 %33, label %35, label %36
35: ; preds = %31
store i32 -1, i32* %3
br label %77
36: ; preds = %31
%37 = call { i16, i1 } @llvm.ssub.with.overflow.i16(i16 32767, i16 1)
%38 = extractvalue { i16, i1 } %37, 1
%39 = extractvalue { i16, i1 } %37, 0
store i16 %39, i16* %6
br i1 %38, label %40, label %41
40: ; preds = %36
store i32 -1, i32* %3
br label %77
41: ; preds = %36
%42 = call { i16, i1 } @llvm.ssub.with.overflow.i16(i16 32767, i16 32767)
%43 = extractvalue { i16, i1 } %42, 1
%44 = extractvalue { i16, i1 } %42, 0
store i16 %44, i16* %6
br i1 %43, label %45, label %46
45: ; preds = %41
store i32 -1, i32* %3
br label %77
46: ; preds = %41
%47 = call { i16, i1 } @llvm.ssub.with.overflow.i16(i16 32767, i16 -32768)
%48 = extractvalue { i16, i1 } %47, 1
%49 = extractvalue { i16, i1 } %47, 0
store i16 %49, i16* %6
br i1 %48, label %51, label %50
50: ; preds = %46
store i32 -1, i32* %3
br label %77
51: ; preds = %46
%52 = call { i16, i1 } @llvm.ssub.with.overflow.i16(i16 32767, i16 -1)
%53 = extractvalue { i16, i1 } %52, 1
%54 = extractvalue { i16, i1 } %52, 0
store i16 %54, i16* %6
br i1 %53, label %56, label %55
55: ; preds = %51
store i32 -1, i32* %3
br label %77
56: ; preds = %51
%57 = call { i16, i1 } @llvm.ssub.with.overflow.i16(i16 -32768, i16 32767)
%58 = extractvalue { i16, i1 } %57, 1
%59 = extractvalue { i16, i1 } %57, 0
store i16 %59, i16* %6
br i1 %58, label %61, label %60
60: ; preds = %56
store i32 -1, i32* %3
br label %77
61: ; preds = %56
%62 = call { i16, i1 } @llvm.ssub.with.overflow.i16(i16 -32768, i16 -32768)
%63 = extractvalue { i16, i1 } %62, 1
%64 = extractvalue { i16, i1 } %62, 0
store i16 %64, i16* %6
br i1 %63, label %65, label %66
65: ; preds = %61
store i32 -1, i32* %3
br label %77
66: ; preds = %61
%67 = call { i16, i1 } @llvm.ssub.with.overflow.i16(i16 -32767, i16 1)
%68 = extractvalue { i16, i1 } %67, 1
%69 = extractvalue { i16, i1 } %67, 0
store i16 %69, i16* %6
br i1 %68, label %70, label %71
70: ; preds = %66
store i32 -1, i32* %3
br label %77
71: ; preds = %66
%72 = call { i16, i1 } @llvm.ssub.with.overflow.i16(i16 -32767, i16 2)
%73 = extractvalue { i16, i1 } %72, 1
%74 = extractvalue { i16, i1 } %72, 0
store i16 %74, i16* %6
br i1 %73, label %76, label %75
75: ; preds = %71
store i32 -1, i32* %3
br label %77
76: ; preds = %71
store i32 0, i32* %3
br label %77
77: ; preds = %76, %75, %70, %65, %60, %55, %50, %45, %40, %35, %30, %25, %20, %15, %10
%78 = load i32, i32* %3
ret i32 %78
}

LLVM IR (-O2):
define i32 @main(i32 %0, i8** nocapture readnone %1) {
ret i32 0
}