int main(int argc, const char **argv) {
  signed char res;
  if (__builtin_add_overflow((signed char)0x0, (signed char)0x0, &res)) {
    return -1;
  }
  if (__builtin_add_overflow((signed char)0x7F, (signed char)0x0, &res)) {
    return -1;
  }
  if (__builtin_add_overflow((signed char)0x0, (signed char)0x7F, &res)) {
    return -1;
  }
  if (__builtin_add_overflow((signed char)0x80, (signed char)0x7F, &res)) {
    return -1;
  }
  if (__builtin_add_overflow((signed char)0x7F, (signed char)0x80, &res)) {
    return -1;
  }
  if (!__builtin_add_overflow((signed char)0x7F, (signed char)0x1, &res)) {
    return -1;
  }
  if (!__builtin_add_overflow((signed char)0x1, (signed char)0x7F, &res)) {
    return -1;
  }
  if (!__builtin_add_overflow((signed char)0x7F, (signed char)0x7F, &res)) {
    return -1;
  }
  if (!__builtin_add_overflow((signed char)0x80, (signed char)0x80, &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    %al,%cl
add    $0x0,%cl
seto   %al
mov    %cl,-0x11(%rbp)
test   $0x1,%al
jne    112c <main+0x2c>
jmp    1138 <main+0x38>
movl   $0xffffffff,-0x4(%rbp)
jmp    124c <main+0x14c>
mov    $0x7f,%cl
add    $0x0,%cl
seto   %al
mov    %cl,-0x11(%rbp)
test   $0x1,%al
jne    1150 <main+0x50>
jmp    115c <main+0x5c>
movl   $0xffffffff,-0x4(%rbp)
jmp    124c <main+0x14c>
xor    %eax,%eax
mov    %al,%cl
add    $0x7f,%cl
seto   %al
mov    %cl,-0x11(%rbp)
test   $0x1,%al
jne    1176 <main+0x76>
jmp    1182 <main+0x82>
movl   $0xffffffff,-0x4(%rbp)
jmp    124c <main+0x14c>
mov    $0x80,%cl
add    $0x7f,%cl
seto   %al
mov    %cl,-0x11(%rbp)
test   $0x1,%al
jne    119a <main+0x9a>
jmp    11a6 <main+0xa6>
movl   $0xffffffff,-0x4(%rbp)
jmp    124c <main+0x14c>
mov    $0x7f,%cl
add    $0x80,%cl
seto   %al
mov    %cl,-0x11(%rbp)
test   $0x1,%al
jne    11be <main+0xbe>
jmp    11ca <main+0xca>
movl   $0xffffffff,-0x4(%rbp)
jmp    124c <main+0x14c>
mov    $0x7f,%cl
inc    %cl
seto   %al
mov    %cl,-0x11(%rbp)
test   $0x1,%al
jne    11e8 <main+0xe8>
movl   $0xffffffff,-0x4(%rbp)
jmp    124c <main+0x14c>
mov    $0x1,%cl
add    $0x7f,%cl
seto   %al
mov    %cl,-0x11(%rbp)
test   $0x1,%al
jne    1207 <main+0x107>
movl   $0xffffffff,-0x4(%rbp)
jmp    124c <main+0x14c>
mov    $0x7f,%cl
add    $0x7f,%cl
seto   %al
mov    %cl,-0x11(%rbp)
test   $0x1,%al
jne    1226 <main+0x126>
movl   $0xffffffff,-0x4(%rbp)
jmp    124c <main+0x14c>
mov    $0x80,%cl
add    $0x80,%cl
seto   %al
mov    %cl,-0x11(%rbp)
test   $0x1,%al
jne    1245 <main+0x145>
movl   $0xffffffff,-0x4(%rbp)
jmp    124c <main+0x14c>
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 i8
store i32 0, i32* %3
store i32 %0, i32* %4
store i8** %1, i8*** %5
%7 = call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 0, i8 0)
%8 = extractvalue { i8, i1 } %7, 1
%9 = extractvalue { i8, i1 } %7, 0
store i8 %9, i8* %6
br i1 %8, label %10, label %11
10: ; preds = %2
store i32 -1, i32* %3
br label %52
11: ; preds = %2
%12 = call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 127, i8 0)
%13 = extractvalue { i8, i1 } %12, 1
%14 = extractvalue { i8, i1 } %12, 0
store i8 %14, i8* %6
br i1 %13, label %15, label %16
15: ; preds = %11
store i32 -1, i32* %3
br label %52
16: ; preds = %11
%17 = call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 0, i8 127)
%18 = extractvalue { i8, i1 } %17, 1
%19 = extractvalue { i8, i1 } %17, 0
store i8 %19, i8* %6
br i1 %18, label %20, label %21
20: ; preds = %16
store i32 -1, i32* %3
br label %52
21: ; preds = %16
%22 = call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 -128, i8 127)
%23 = extractvalue { i8, i1 } %22, 1
%24 = extractvalue { i8, i1 } %22, 0
store i8 %24, i8* %6
br i1 %23, label %25, label %26
25: ; preds = %21
store i32 -1, i32* %3
br label %52
26: ; preds = %21
%27 = call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 127, i8 -128)
%28 = extractvalue { i8, i1 } %27, 1
%29 = extractvalue { i8, i1 } %27, 0
store i8 %29, i8* %6
br i1 %28, label %30, label %31
30: ; preds = %26
store i32 -1, i32* %3
br label %52
31: ; preds = %26
%32 = call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 127, i8 1)
%33 = extractvalue { i8, i1 } %32, 1
%34 = extractvalue { i8, i1 } %32, 0
store i8 %34, i8* %6
br i1 %33, label %36, label %35
35: ; preds = %31
store i32 -1, i32* %3
br label %52
36: ; preds = %31
%37 = call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 1, i8 127)
%38 = extractvalue { i8, i1 } %37, 1
%39 = extractvalue { i8, i1 } %37, 0
store i8 %39, i8* %6
br i1 %38, label %41, label %40
40: ; preds = %36
store i32 -1, i32* %3
br label %52
41: ; preds = %36
%42 = call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 127, i8 127)
%43 = extractvalue { i8, i1 } %42, 1
%44 = extractvalue { i8, i1 } %42, 0
store i8 %44, i8* %6
br i1 %43, label %46, label %45
45: ; preds = %41
store i32 -1, i32* %3
br label %52
46: ; preds = %41
%47 = call { i8, i1 } @llvm.sadd.with.overflow.i8(i8 -128, i8 -128)
%48 = extractvalue { i8, i1 } %47, 1
%49 = extractvalue { i8, i1 } %47, 0
store i8 %49, i8* %6
br i1 %48, label %51, label %50
50: ; preds = %46
store i32 -1, i32* %3
br label %52
51: ; preds = %46
store i32 0, i32* %3
br label %52
52: ; preds = %51, %50, %45, %40, %35, %30, %25, %20, %15, %10
%53 = load i32, i32* %3
ret i32 %53
}

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