#define NULL ((void *)0)
typedef unsigned long size_t; // Customize by platform.
typedef long intptr_t;
typedef unsigned long uintptr_t;
typedef long scalar_t__; // Either arithmetic or pointer type.
/* By default, we understand bool (as a convenience). */
typedef int bool;
#define false 0
#define true 1

/* Forward declarations */

/* Type definitions */

/* Variables and functions */
int O_CREAT;
int O_WRONLY;
int S_IRUSR;
int S_IWUSR;
int /*<<< orphan*/ close(int);
int /*<<< orphan*/ dup2(int, int);
int /*<<< orphan*/ exit(int);
int /*<<< orphan*/ fprintf(int /*<<< orphan*/, char *, ...);
int open(char *, int, int);
int /*<<< orphan*/ printf(char *, char *);
int /*<<< orphan*/ stderr;
int main(int argc, char *argv[]) {
  int fd;
  if (argc != 2) {
    fprintf(stderr, "Usage: %s message\n", argv[0]);
    exit(1);
  }
  if ((fd = open("prank.txt", O_WRONLY | O_CREAT, S_IRUSR | S_IWUSR)) == -1) {
    fprintf(stderr, "Failed to open prank.txt for writing: %m\n");
    exit(1);
  }
  dup2(fd, 1);
  close(fd);
  printf("%s\n", argv[1]);
  return 0;
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0x20,%rsp
movl   $0x0,-0x4(%rbp)
mov    %edi,-0x8(%rbp)
mov    %rsi,-0x10(%rbp)
cmpl   $0x2,-0x8(%rbp)
je     11a8 <main+0x48>
mov    0x2e49(%rip),%rax
mov    (%rax),%edi
mov    -0x10(%rbp),%rax
mov    (%rax),%rdx
lea    0xe69(%rip),%rsi
mov    $0x0,%al
call   1060 <fprintf@plt>
mov    $0x1,%edi
call   1080 <exit@plt>
mov    0x2e09(%rip),%rax
mov    (%rax),%esi
mov    0x2e40(%rip),%rax
or     (%rax),%esi
mov    0x2e07(%rip),%rax
mov    (%rax),%edx
mov    0x2e16(%rip),%rax
or     (%rax),%edx
lea    0xe40(%rip),%rdi
call   1070 <open@plt>
mov    %eax,-0x14(%rbp)
cmp    $0xffffffff,%eax
jne    1205 <main+0xa5>
mov    0x2de5(%rip),%rax
mov    (%rax),%edi
lea    0xe29(%rip),%rsi
mov    $0x0,%al
call   1060 <fprintf@plt>
mov    $0x1,%edi
call   1080 <exit@plt>
mov    -0x14(%rbp),%edi
mov    $0x1,%esi
call   1030 <dup2@plt>
mov    -0x14(%rbp),%edi
call   1050 <close@plt>
mov    -0x10(%rbp),%rax
mov    0x8(%rax),%rsi
lea    0xe1e(%rip),%rdi
call   1040 <printf@plt>
xor    %eax,%eax
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %rbp
push   %rbx
push   %rax
mov    %rsi,%rbx
cmp    $0x2,%edi
jne    11ce <main+0x6e>
mov    0x2e46(%rip),%rax
mov    0x2e7f(%rip),%rcx
mov    (%rcx),%esi
or     (%rax),%esi
mov    0x2e44(%rip),%rax
mov    0x2e55(%rip),%rcx
mov    (%rcx),%edx
or     (%rax),%edx
lea    0xe7d(%rip),%rdi
call   1070 <open@plt>
cmp    $0xffffffff,%eax
je     11f2 <main+0x92>
mov    %eax,%ebp
mov    %eax,%edi
mov    $0x1,%esi
call   1030 <dup2@plt>
mov    %ebp,%edi
call   1050 <close@plt>
mov    0x8(%rbx),%rsi
lea    0xe87(%rip),%rdi
call   1040 <printf@plt>
xor    %eax,%eax
add    $0x8,%rsp
pop    %rbx
pop    %rbp
ret
mov    0x2dfb(%rip),%rax
mov    (%rax),%edi
mov    (%rbx),%rdx
lea    0xe1f(%rip),%rsi
xor    %eax,%eax
call   1060 <fprintf@plt>
mov    $0x1,%edi
call   1080 <exit@plt>
mov    0x2dd7(%rip),%rax
mov    (%rax),%edi
lea    0xe1b(%rip),%rsi
xor    %eax,%eax
call   1060 <fprintf@plt>
mov    $0x1,%edi
call   1080 <exit@plt>

LLVM IR (-O0):
@stderr = global i32 0
@.str = [19 x i8] c"Usage: %s message\0A\00"
@.str.1 = [10 x i8] c"prank.txt\00"
@O_WRONLY = global i32 0
@O_CREAT = global i32 0
@S_IRUSR = global i32 0
@S_IWUSR = global i32 0
@.str.2 = [42 x i8] c"Failed to open prank.txt for writing: %m\0A\00"
@.str.3 = [4 x i8] c"%s\0A\00"
define i32 @main(i32 %0, i8** %1) {
%3 = alloca i32
%4 = alloca i32
%5 = alloca i8**
%6 = alloca i32
store i32 0, i32* %3
store i32 %0, i32* %4
store i8** %1, i8*** %5
%7 = load i32, i32* %4
%8 = icmp ne i32 %7, 2
br i1 %8, label %9, label %16
9: ; preds = %2
%10 = load i32, i32* @stderr
%11 = load i8**, i8*** %5
%12 = getelementptr inbounds i8*, i8** %11, i64 0
%13 = load i8*, i8** %12
%14 = call i32 (i32, i8*, ...) @fprintf(i32 %10, i8* getelementptr inbounds ([19 x i8], [19 x i8]* @.str, i64 0, i64 0), i8* %13)
%15 = call i32 @exit(i32 1)
unreachable
16: ; preds = %2
%17 = load i32, i32* @O_WRONLY
%18 = load i32, i32* @O_CREAT
%19 = or i32 %17, %18
%20 = load i32, i32* @S_IRUSR
%21 = load i32, i32* @S_IWUSR
%22 = or i32 %20, %21
%23 = call i32 @open(i8* getelementptr inbounds ([10 x i8], [10 x i8]* @.str.1, i64 0, i64 0), i32 %19, i32 %22)
store i32 %23, i32* %6
%24 = icmp eq i32 %23, -1
br i1 %24, label %25, label %29
25: ; preds = %16
%26 = load i32, i32* @stderr
%27 = call i32 (i32, i8*, ...) @fprintf(i32 %26, i8* getelementptr inbounds ([42 x i8], [42 x i8]* @.str.2, i64 0, i64 0))
%28 = call i32 @exit(i32 1)
unreachable
29: ; preds = %16
%30 = load i32, i32* %6
%31 = call i32 @dup2(i32 %30, i32 1)
%32 = load i32, i32* %6
%33 = call i32 @close(i32 %32)
%34 = load i8**, i8*** %5
%35 = getelementptr inbounds i8*, i8** %34, i64 1
%36 = load i8*, i8** %35
%37 = call i32 @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str.3, i64 0, i64 0), i8* %36)
ret i32 0
}

LLVM IR (-O2):
@stderr = global i32 0
@.str = [19 x i8] c"Usage: %s message\0A\00"
@.str.1 = [10 x i8] c"prank.txt\00"
@O_WRONLY = global i32 0
@O_CREAT = global i32 0
@S_IRUSR = global i32 0
@S_IWUSR = global i32 0
@.str.2 = [42 x i8] c"Failed to open prank.txt for writing: %m\0A\00"
@.str.3 = [4 x i8] c"%s\0A\00"
define i32 @main(i32 %0, i8** nocapture %1) {
%3 = icmp eq i32 %0, 2
br i1 %3, label %9, label %4
4: ; preds = %2
%5 = load i32, i32* @stderr
%6 = load i8*, i8** %1
%7 = tail call i32 (i32, i8*, ...) @fprintf(i32 %5, i8* getelementptr inbounds ([19 x i8], [19 x i8]* @.str, i64 0, i64 0), i8* %6)
%8 = tail call i32 @exit(i32 1)
unreachable
9: ; preds = %2
%10 = load i32, i32* @O_WRONLY
%11 = load i32, i32* @O_CREAT
%12 = or i32 %11, %10
%13 = load i32, i32* @S_IRUSR
%14 = load i32, i32* @S_IWUSR
%15 = or i32 %14, %13
%16 = tail call i32 @open(i8* getelementptr inbounds ([10 x i8], [10 x i8]* @.str.1, i64 0, i64 0), i32 %12, i32 %15)
%17 = icmp eq i32 %16, -1
br i1 %17, label %18, label %22
18: ; preds = %9
%19 = load i32, i32* @stderr
%20 = tail call i32 (i32, i8*, ...) @fprintf(i32 %19, i8* getelementptr inbounds ([42 x i8], [42 x i8]* @.str.2, i64 0, i64 0))
%21 = tail call i32 @exit(i32 1)
unreachable
22: ; preds = %9
%23 = tail call i32 @dup2(i32 %16, i32 1)
%24 = tail call i32 @close(i32 %16)
%25 = getelementptr inbounds i8*, i8** %1, i64 1
%26 = load i8*, i8** %25
%27 = tail call i32 @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str.3, i64 0, i64 0), i8* %26)
ret i32 0
}