#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 */
char *getenv(char *);
int /*<<< orphan*/ printf(char *, char *);
int /*<<< orphan*/ setenv(char *, char *, int);
int main(int argc, char *argv[]) {
  printf("PATH = %s\n", getenv("PATH"));
  printf("HOME = %s\n", getenv("HOME"));
  printf("TZ = %s\n", getenv("TZ"));
  setenv("MY", "YOU", 1);
  printf("MY = %s\n", getenv("MY"));
  return 0;
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0x10,%rsp
movl   $0x0,-0x4(%rbp)
mov    %edi,-0x8(%rbp)
mov    %rsi,-0x10(%rbp)
lea    0xebe(%rip),%rdi
call   1030 <getenv@plt>
mov    %rax,%rsi
lea    0xea4(%rip),%rdi
call   1050 <printf@plt>
lea    0xeb3(%rip),%rdi
call   1030 <getenv@plt>
mov    %rax,%rsi
lea    0xe99(%rip),%rdi
call   1050 <printf@plt>
lea    0xea6(%rip),%rdi
call   1030 <getenv@plt>
mov    %rax,%rsi
lea    0xe8e(%rip),%rdi
call   1050 <printf@plt>
lea    0xe8e(%rip),%rdi
lea    0xe8a(%rip),%rsi
mov    $0x1,%edx
call   1040 <setenv@plt>
lea    0xe76(%rip),%rdi
call   1030 <getenv@plt>
mov    %rax,%rsi
lea    0xe6e(%rip),%rdi
call   1050 <printf@plt>
xor    %eax,%eax
add    $0x10,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %rbx
lea    0xed3(%rip),%rdi
call   1030 <getenv@plt>
lea    0xebc(%rip),%rdi
mov    %rax,%rsi
call   1050 <printf@plt>
lea    0xec8(%rip),%rdi
call   1030 <getenv@plt>
lea    0xeb1(%rip),%rdi
mov    %rax,%rsi
call   1050 <printf@plt>
lea    0xebb(%rip),%rdi
call   1030 <getenv@plt>
lea    0xea6(%rip),%rdi
mov    %rax,%rsi
call   1050 <printf@plt>
lea    0xea3(%rip),%rbx
lea    0xe9f(%rip),%rsi
mov    %rbx,%rdi
mov    $0x1,%edx
call   1040 <setenv@plt>
mov    %rbx,%rdi
call   1030 <getenv@plt>
lea    0xe87(%rip),%rdi
mov    %rax,%rsi
call   1050 <printf@plt>
xor    %eax,%eax
pop    %rbx
ret

LLVM IR (-O0):
@.str = [11 x i8] c"PATH = %s\0A\00"
@.str.1 = [5 x i8] c"PATH\00"
@.str.2 = [11 x i8] c"HOME = %s\0A\00"
@.str.3 = [5 x i8] c"HOME\00"
@.str.4 = [9 x i8] c"TZ = %s\0A\00"
@.str.5 = [3 x i8] c"TZ\00"
@.str.6 = [3 x i8] c"MY\00"
@.str.7 = [4 x i8] c"YOU\00"
@.str.8 = [9 x i8] c"MY = %s\0A\00"
define i32 @main(i32 %0, i8** %1) {
%3 = alloca i32
%4 = alloca i32
%5 = alloca i8**
store i32 0, i32* %3
store i32 %0, i32* %4
store i8** %1, i8*** %5
%6 = call i8* @getenv(i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str.1, i64 0, i64 0))
%7 = call i32 @printf(i8* getelementptr inbounds ([11 x i8], [11 x i8]* @.str, i64 0, i64 0), i8* %6)
%8 = call i8* @getenv(i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str.3, i64 0, i64 0))
%9 = call i32 @printf(i8* getelementptr inbounds ([11 x i8], [11 x i8]* @.str.2, i64 0, i64 0), i8* %8)
%10 = call i8* @getenv(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.5, i64 0, i64 0))
%11 = call i32 @printf(i8* getelementptr inbounds ([9 x i8], [9 x i8]* @.str.4, i64 0, i64 0), i8* %10)
%12 = call i32 @setenv(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.6, i64 0, i64 0), i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str.7, i64 0, i64 0), i32 1)
%13 = call i8* @getenv(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.6, i64 0, i64 0))
%14 = call i32 @printf(i8* getelementptr inbounds ([9 x i8], [9 x i8]* @.str.8, i64 0, i64 0), i8* %13)
ret i32 0
}

LLVM IR (-O2):
@.str = [11 x i8] c"PATH = %s\0A\00"
@.str.1 = [5 x i8] c"PATH\00"
@.str.2 = [11 x i8] c"HOME = %s\0A\00"
@.str.3 = [5 x i8] c"HOME\00"
@.str.4 = [9 x i8] c"TZ = %s\0A\00"
@.str.5 = [3 x i8] c"TZ\00"
@.str.6 = [3 x i8] c"MY\00"
@.str.7 = [4 x i8] c"YOU\00"
@.str.8 = [9 x i8] c"MY = %s\0A\00"
define i32 @main(i32 %0, i8** nocapture readnone %1) {
%3 = tail call i8* @getenv(i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str.1, i64 0, i64 0))
%4 = tail call i32 @printf(i8* getelementptr inbounds ([11 x i8], [11 x i8]* @.str, i64 0, i64 0), i8* %3)
%5 = tail call i8* @getenv(i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str.3, i64 0, i64 0))
%6 = tail call i32 @printf(i8* getelementptr inbounds ([11 x i8], [11 x i8]* @.str.2, i64 0, i64 0), i8* %5)
%7 = tail call i8* @getenv(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.5, i64 0, i64 0))
%8 = tail call i32 @printf(i8* getelementptr inbounds ([9 x i8], [9 x i8]* @.str.4, i64 0, i64 0), i8* %7)
%9 = tail call i32 @setenv(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.6, i64 0, i64 0), i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str.7, i64 0, i64 0), i32 1)
%10 = tail call i8* @getenv(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.6, i64 0, i64 0))
%11 = tail call i32 @printf(i8* getelementptr inbounds ([9 x i8], [9 x i8]* @.str.8, i64 0, i64 0), i8* %10)
ret i32 0
}