Is wordexp in libc on OSX 10.9.5 known to leak?

问题

Is wordexp on OSX 10.9.5 known to leak memory? And if not, what is wrong with my code?

On my own local machine running OSX 10.10.5 I run my code through Valgrind and get no lost bytes.

No leaks on my Ubuntu Linux machine either.

However, when I turned on valgrind checks on my travis-ci account that uses OSX 10.9.5 I suddenly get a leak from memory allocated inside of wordexp even though I free it using wordfree as the man page describes:

==8968== LEAK SUMMARY:
==8968==    definitely lost: 1,024 bytes in 1 blocks
==8968==    indirectly lost: 0 bytes in 0 blocks
==8968==      possibly lost: 0 bytes in 0 blocks

OSX 10.9.5 uname output:

Darwin 13.4.0 Darwin Kernel Version 13.4.0: Sun Aug 17 19:50:11 PDT 2014; root:xnu-2422.115.4~1/RELEASE_X86_64 x86_64

OSX 10.9.5 sw_vers output:

ProductName:    Mac OS X
ProductVersion: 10.9.5
BuildVersion:   13F34

OSX 10.9.5 libc version 1197.1.1 otool -L /usr/lib/libSystem.dylib:

/usr/lib/libSystem.dylib:
    /usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 1197.1.1)

OSX 10.10.5 libc version 1213.0.0:

/usr/lib/libSystem.dylib:
    /usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 1213.0.0)

Relevant code (Please use the link to the full code below if compiling): https://github.com/JoakimSoderberg/wordexp_test

static void xfree(void *p)
{
    void **pp;
    assert(p);

    pp = (void **)p;

    if (*pp)
    {
        free(*pp);
        *pp = NULL;
    }
}

char **test_wordexp(const char *cmdline, int *argc)
{
    char **argv = NULL;
    size_t i;
    int ret;
    wordexp_t p;
    memset(&p, 0, sizeof(p));

    // Note! This expands shell variables.
    if ((ret = wordexp(cmdline, &p, 0)))
    {
        fprintf(stderr, "wordexp error %d: '%s'\n", ret, cmdline);
        return NULL;
    }

    *argc = p.we_wordc;

    if (!(argv = calloc(*argc, sizeof(char *))))
    {
        fprintf(stderr, "Out of memory!\n");
        goto fail;
    }

    for (i = 0; i < p.we_wordc; i++)
    {
        if (!(argv[i] = strdup(p.we_wordv[i])))
        {
            fprintf(stderr, "Out of memory!\n");
            goto fail;
        }
    }

    wordfree(&p);

    return argv;

fail:
    wordfree(&p);

    if (argv)
    {
        for (i = 0; i < (size_t)*argc; i++)
        {
            xfree(&argv[i]);
        }

        free(argv);
    }

    return NULL;
}

Full code: https://github.com/JoakimSoderberg/wordexp_test

Travis job with failed OSX but successful Linux:

https://travis-ci.org/JoakimSoderberg/wordexp_test/builds/83194932

Exact line of OSX Travis job with leak error:

https://travis-ci.org/JoakimSoderberg/wordexp_test/jobs/83194937#L78

The wordexp is known on OSX for having used Perl in its implementation. But apparently doesn't any more.