56 lines
1.5 KiB
C++
56 lines
1.5 KiB
C++
//===-- main.cpp ------------------------------------------------*- C++ -*-===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
// This file deliberately uses low level linux-specific API for thread creation because:
|
|
// - instruction-stepping over thread creation using higher-level functions was very slow
|
|
// - it was also unreliable due to single-stepping bugs unrelated to this test
|
|
// - some threading libraries do not create or destroy threads when we would expect them to
|
|
|
|
#include <sched.h>
|
|
|
|
#include <atomic>
|
|
#include <cstdio>
|
|
|
|
enum { STACK_SIZE = 0x2000 };
|
|
|
|
static uint8_t child_stack[STACK_SIZE];
|
|
|
|
pid_t child_tid;
|
|
|
|
std::atomic<bool> flag(false);
|
|
|
|
int thread_main(void *)
|
|
{
|
|
while (! flag) // Make sure the thread does not exit prematurely
|
|
;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int main ()
|
|
{
|
|
int ret = clone(thread_main,
|
|
child_stack + STACK_SIZE/2, // Don't care whether the stack grows up or down,
|
|
// just point to the middle
|
|
CLONE_CHILD_CLEARTID | CLONE_FILES | CLONE_FS | CLONE_PARENT_SETTID |
|
|
CLONE_SIGHAND | CLONE_SYSVSEM | CLONE_THREAD | CLONE_VM,
|
|
nullptr, // thread_main argument
|
|
&child_tid);
|
|
|
|
if (ret == -1)
|
|
{
|
|
perror("clone");
|
|
return 1;
|
|
}
|
|
|
|
flag = true;
|
|
|
|
return 0;
|
|
}
|