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// Check that if LSan finds that SP doesn't point into thread stack (e.g.
// if swapcontext is used), LSan will not hit the guard page.
// RUN: %clang_lsan %s -o %t && %run %t
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <pthread.h>
#include <ucontext.h>
pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
int ctxfunc_started = 0;
static void die(const char* msg, int err) {
if (err == 0)
err = errno;
fprintf(stderr, "%s: %s\n", msg, strerror(err));
exit(EXIT_FAILURE);
}
static void ctxfunc() {
pthread_mutex_lock(&mutex);
ctxfunc_started = 1;
pthread_cond_signal(&cond);
pthread_mutex_unlock(&mutex);
// Leave this context alive when the program exits.
for (;;);
}
static void* thread(void* arg) {
(void)arg;
ucontext_t ctx;
void* stack;
if (getcontext(&ctx) < 0)
die("getcontext", 0);
stack = malloc(1 << 10);
if (stack == NULL)
die("malloc", 0);
ctx.uc_stack.ss_sp = stack;
ctx.uc_stack.ss_size = 1 << 10;
makecontext(&ctx, ctxfunc, 0);
setcontext(&ctx);
die("setcontext", 0);
return NULL;
}
int main() {
pthread_t tid;
int i;
pthread_mutex_lock(&mutex);
i = pthread_create(&tid, NULL, thread, NULL);
if (i != 0)
die("pthread_create", i);
while (!ctxfunc_started) pthread_cond_wait(&cond, &mutex);
pthread_mutex_unlock(&mutex);
return 0;
}
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