Test openblas use of compiler's TLS to not deadlock on dl_close

test_compiler_tls.c

/* Build with gcc test_compiler_tls.c -o test_compiler_tls -ldl -g -pthread */

#include <dlfcn.h>
#include <stdio.h>
#include <pthread.h>
#include <time.h>
#include <sys/time.h>
#include <stdint.h>

pthread_cond_t cond;

void* test_thread(void* arg) {
        const char* filename = (const char*) arg;
        int i;
        intptr_t ret = 0;

        for(i = 0; i < 10; i++) {
                printf("Try %d\n", i);
                void* handle = dlopen(filename, RTLD_NOW);
                if(handle == 0) {
                        printf("Can't open openblas: %s\n", dlerror());
                        ret = 1;
                        break;
                }
                dlclose(handle);
        }

        pthread_cond_signal(&cond);

        return (void*) ret;
}

int main(int argc, char* argv[]) {
        pthread_t thread;
        pthread_mutex_t mutex;
        struct timespec timeToWait;
        struct timeval now;
        int ret;

        pthread_mutex_init(&mutex, NULL);
        pthread_cond_init(&cond, NULL);

        if(argc < 2) {
                printf("Usage: %s libopenblas.so\n", argv[0]);
                return 1;
        }

        pthread_create(&thread, NULL, &test_thread, argv[1]);

        gettimeofday(&now, NULL);
        /* 10s timeout */
        timeToWait.tv_sec = now.tv_sec + 10;
        timeToWait.tv_nsec = now.tv_usec * 1000UL;

        pthread_mutex_lock(&mutex);
        ret = pthread_cond_timedwait(&cond, &mutex, &timeToWait);
        if(ret != 0) {
                printf("Failed to wait end of test thread, deadlocked ?: %d\n", ret);
                return 2;
        } else {
                void* threadRet;
                pthread_join(thread, &threadRet);
                if((intptr_t)threadRet != 0) {
                        printf("test_thread failed\n");
                        return 3;
                }
                return 0;
        }
}