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#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include <time.h>
#include <dlfcn.h>

__thread volatile int tls __attribute__((tls_model("global-dynamic")));

static int __attribute__ ((noinline)) readtls(void) { return tls; }

static void __attribute__ ((noinline)) writetls(int v) { tls = v; }


int main(void)
{
	volatile int i;
	time_t ts;

	dlopen("libuuid.so.1.3.0", RTLD_NOW);

	ts = time(NULL);
	writetls(0);
	for (i = 1; i < 0x2000000; ++i) {
		volatile int j = readtls();
		assert(j + 1 == i);
		writetls(i);
	}
	printf("Time used: %lu\n", time(NULL) - ts);
	return 0;
}