#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 MS_BIND;
int MS_REC;
int MS_SLAVE;
int /*<<< orphan*/ execlp(char *, char *, char *);
scalar_t__ getpid();
scalar_t__ getppid();
int /*<<< orphan*/ mount(char *, char *, char *, int, int /*<<< orphan*/ *);
int /*<<< orphan*/ printf(char *, long);
int /*<<< orphan*/ sethostname(char *, int /*<<< orphan*/);
int /*<<< orphan*/ strlen(char *);
int /*<<< orphan*/ umount(char *);
int child(void *arg) {
  char *newhostname = arg;
  sethostname(newhostname, strlen(newhostname));
  printf("My PID: %ld\n", (long)getpid());
  printf("My PPID: %ld\n", (long)getppid());
  mount("", "/", "dontcare", MS_REC | MS_SLAVE | MS_BIND, NULL);
  umount("/proc");
  mount("proc", "/proc", "proc", 0, NULL);
  execlp("bash", "bash", (char *)NULL);
  return 0;
}


x86 assembly (clang, -O0):
<child>:
push   %rbp
mov    %rsp,%rbp
sub    $0x20,%rsp
mov    %rdi,-0x8(%rbp)
mov    -0x8(%rbp),%rax
mov    %rax,-0x10(%rbp)
mov    -0x10(%rbp),%rax
mov    %rax,-0x18(%rbp)
mov    -0x10(%rbp),%rdi
call   1050 <strlen@plt>
mov    -0x18(%rbp),%rdi
mov    %eax,%esi
call   1080 <sethostname@plt>
mov    $0x0,%al
call   1040 <getpid@plt>
mov    %rax,%rsi
lea    0xe3f(%rip),%rdi
call   1070 <printf@plt>
mov    $0x0,%al
call   1090 <getppid@plt>
mov    %rax,%rsi
lea    0xe36(%rip),%rdi
call   1070 <printf@plt>
mov    0x2dfd(%rip),%rax
mov    (%rax),%ecx
mov    0x2de4(%rip),%rax
or     (%rax),%ecx
mov    0x2df3(%rip),%rax
or     (%rax),%ecx
lea    0xe0e(%rip),%rdi
lea    0xe16(%rip),%rsi
lea    0xe11(%rip),%rdx
xor    %eax,%eax
mov    %eax,%r8d
call   1060 <mount@plt>
lea    0xe09(%rip),%rdi
call   1030 <umount@plt>
lea    0xdfe(%rip),%rdx
lea    0xdf6(%rip),%rsi
xor    %ecx,%ecx
xor    %eax,%eax
mov    %eax,%r8d
mov    %rdx,%rdi
call   1060 <mount@plt>
lea    0xde6(%rip),%rsi
xor    %eax,%eax
mov    %eax,%edx
mov    %rsi,%rdi
call   10a0 <execlp@plt>
xor    %eax,%eax
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<child>:
push   %rbx
mov    %rdi,%rbx
call   1050 <strlen@plt>
mov    %rbx,%rdi
mov    %eax,%esi
call   1080 <sethostname@plt>
xor    %eax,%eax
call   1040 <getpid@plt>
lea    0xe5f(%rip),%rdi
mov    %rax,%rsi
call   1070 <printf@plt>
xor    %eax,%eax
call   1090 <getppid@plt>
lea    0xe56(%rip),%rdi
mov    %rax,%rsi
call   1070 <printf@plt>
mov    0x2e1a(%rip),%rax
mov    0x2e03(%rip),%rcx
mov    (%rcx),%ecx
or     (%rax),%ecx
mov    0x2e10(%rip),%rax
or     (%rax),%ecx
lea    0xe2b(%rip),%rdi
lea    0xe33(%rip),%rsi
lea    0xe2e(%rip),%rdx
xor    %r8d,%r8d
call   1060 <mount@plt>
lea    0xe28(%rip),%rbx
mov    %rbx,%rdi
call   1030 <umount@plt>
lea    0xe1a(%rip),%rdi
mov    %rbx,%rsi
mov    %rdi,%rdx
xor    %ecx,%ecx
xor    %r8d,%r8d
call   1060 <mount@plt>
lea    0xe08(%rip),%rdi
mov    %rdi,%rsi
xor    %edx,%edx
call   10a0 <execlp@plt>
xor    %eax,%eax
pop    %rbx
ret

LLVM IR (-O0):
@.str = [13 x i8] c"My PID: %ld\0A\00"
@.str.1 = [14 x i8] c"My PPID: %ld\0A\00"
@.str.2 = [1 x i8] zeroinitializer
@.str.3 = [2 x i8] c"/\00"
@.str.4 = [9 x i8] c"dontcare\00"
@MS_REC = global i32 0
@MS_SLAVE = global i32 0
@MS_BIND = global i32 0
@.str.5 = [6 x i8] c"/proc\00"
@.str.6 = [5 x i8] c"proc\00"
@.str.7 = [5 x i8] c"bash\00"
define i32 @child(i8* %0) {
%2 = alloca i8*
%3 = alloca i8*
store i8* %0, i8** %2
%4 = load i8*, i8** %2
store i8* %4, i8** %3
%5 = load i8*, i8** %3
%6 = load i8*, i8** %3
%7 = call i32 @strlen(i8* %6)
%8 = call i32 @sethostname(i8* %5, i32 %7)
%9 = call i64 (...) @getpid()
%10 = call i32 @printf(i8* getelementptr inbounds ([13 x i8], [13 x i8]* @.str, i64 0, i64 0), i64 %9)
%11 = call i64 (...) @getppid()
%12 = call i32 @printf(i8* getelementptr inbounds ([14 x i8], [14 x i8]* @.str.1, i64 0, i64 0), i64 %11)
%13 = load i32, i32* @MS_REC
%14 = load i32, i32* @MS_SLAVE
%15 = or i32 %13, %14
%16 = load i32, i32* @MS_BIND
%17 = or i32 %15, %16
%18 = call i32 @mount(i8* getelementptr inbounds ([1 x i8], [1 x i8]* @.str.2, i64 0, i64 0), i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str.3, i64 0, i64 0), i8* getelementptr inbounds ([9 x i8], [9 x i8]* @.str.4, i64 0, i64 0), i32 %17, i32* null)
%19 = call i32 @umount(i8* getelementptr inbounds ([6 x i8], [6 x i8]* @.str.5, i64 0, i64 0))
%20 = call i32 @mount(i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str.6, i64 0, i64 0), i8* getelementptr inbounds ([6 x i8], [6 x i8]* @.str.5, i64 0, i64 0), i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str.6, i64 0, i64 0), i32 0, i32* null)
%21 = call i32 @execlp(i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str.7, i64 0, i64 0), i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str.7, i64 0, i64 0), i8* null)
ret i32 0
}

LLVM IR (-O2):
@.str = [13 x i8] c"My PID: %ld\0A\00"
@.str.1 = [14 x i8] c"My PPID: %ld\0A\00"
@.str.2 = [1 x i8] zeroinitializer
@.str.3 = [2 x i8] c"/\00"
@.str.4 = [9 x i8] c"dontcare\00"
@MS_REC = global i32 0
@MS_SLAVE = global i32 0
@MS_BIND = global i32 0
@.str.5 = [6 x i8] c"/proc\00"
@.str.6 = [5 x i8] c"proc\00"
@.str.7 = [5 x i8] c"bash\00"
define i32 @child(i8* %0) {
%2 = tail call i32 @strlen(i8* %0)
%3 = tail call i32 @sethostname(i8* %0, i32 %2)
%4 = tail call i64 (...) @getpid()
%5 = tail call i32 @printf(i8* getelementptr inbounds ([13 x i8], [13 x i8]* @.str, i64 0, i64 0), i64 %4)
%6 = tail call i64 (...) @getppid()
%7 = tail call i32 @printf(i8* getelementptr inbounds ([14 x i8], [14 x i8]* @.str.1, i64 0, i64 0), i64 %6)
%8 = load i32, i32* @MS_REC
%9 = load i32, i32* @MS_SLAVE
%10 = or i32 %9, %8
%11 = load i32, i32* @MS_BIND
%12 = or i32 %10, %11
%13 = tail call i32 @mount(i8* getelementptr inbounds ([1 x i8], [1 x i8]* @.str.2, i64 0, i64 0), i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str.3, i64 0, i64 0), i8* getelementptr inbounds ([9 x i8], [9 x i8]* @.str.4, i64 0, i64 0), i32 %12, i32* null)
%14 = tail call i32 @umount(i8* getelementptr inbounds ([6 x i8], [6 x i8]* @.str.5, i64 0, i64 0))
%15 = tail call i32 @mount(i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str.6, i64 0, i64 0), i8* getelementptr inbounds ([6 x i8], [6 x i8]* @.str.5, i64 0, i64 0), i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str.6, i64 0, i64 0), i32 0, i32* null)
%16 = tail call i32 @execlp(i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str.7, i64 0, i64 0), i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str.7, i64 0, i64 0), i8* null)
ret i32 0
}