Snippet from iscsi-test-cu.c that triggers a segfault when built with gcc 4.9

libiscsi-null-ptr-deref.c

#include <assert.h>
#include <ctype.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>


static int
add_tests(const char *testname_re)
{
	if (!testname_re)
		printf("OK\n");
	else
		assert(testname_re == NULL);

	return 0;
}

static void parse_and_add_tests(char *testname_re);

static void parse_and_add_test(char *test)
{
	if (access(test, F_OK) == 0) {
		/* Not executed because access(NULL, F_OK) returns -1 */
		FILE *fh;
		char t[256];

		if ((fh = fopen(test, "r")) == NULL)
			exit(1);
		while (fgets(t, sizeof(t), fh) != NULL) {
			while (1) {
				int len = strlen(t);
				if (len == 0) {
					break;
				}
				if (!isprint(t[--len])) {
					t[len] = 0;
					continue;
				}
				break;	
			}
			/* Commenting out this instruction makes the program work */
			parse_and_add_tests(t);
		}
		fclose(fh);
		return;
	}

	if (add_tests(test) != 0)
		exit(1);
}

static void parse_and_add_tests(char *testname_re)
{
	parse_and_add_test(testname_re);
}

int main(void)
{
	parse_and_add_tests(NULL);

	return 0;
}