debugging M4 on AIX 5.3

[Ralf Wildenhues]

I'm trying to debug the recent regression of git branch-1.4 M4 over M4
1.4.14 on AIX.  First the gnulib stuff.

Notes:

- 2 gnulib test failures in M4: test-strtod, test-rmdir.

I inserted one fprintf in test-strtod.c, for the "0xp" input asserting
over 'ptr == input + 1':

    const char input[] = "0xp";
    char *ptr;
    double result;
    errno = 0;
    result = strtod (input, &ptr);
    ASSERT (result == 0.0);
    ASSERT (!signbit (result));
    fprintf (stderr, "ptr is %lu, input + 1 is %lu\n", (unsigned long) ptr, 
(unsigned long) input + 1);
    ASSERT (ptr == input + 1);          /* glibc-2.3.6, MacOS X 10.3, FreeBSD 
6.2, AIX 7.1 */
    ASSERT (errno == 0);


$ ./test-strtod
ptr is 804398203, input + 1 is 804398201
../../m4/tests/test-strtod.c:434: assertion failed
zsh: abort (core dumped)  ./test-strtod


I inserted one fprintf in test-rmdir.h, for the empty directory errno
test:
  ASSERT (func (BASE "dir/.//") == -1);
  fprintf (stderr, "errno = %d, %s\n", errno, strerror(errno) );
  ASSERT (errno == EINVAL || errno == EBUSY);

$ ./test-rmdir
errno = 17, File exists
../../m4/tests/test-rmdir.h:70: assertion failed
zsh: abort (core dumped)  ./test-rmdir


In 1.4.14, only the latter fails, at the same position.


- 'gnulib-tool --with-tests --test strtod rmdir' passes on this system.

- 'gnulib-tool --with-tests --dir=strtod --test announce-gen assert autobuild 
avltree-oset binary-io c-stack clean-temp cloexec close-stream closein config-h 
dirname error execute fdl-1.3 fflush filenamecat fopen fopen-safer fseeko 
gendocs getopt-gnu git-version-gen gnu-web-doc-update gnumakefile gnupload 
gpl-3.0 ignore-value intprops maintainer-makefile manywarnings memchr2 mkstemp 
obstack pipe progname regex sigaction stdbool stdint stdlib-safer strsignal 
strstr strtod strtol unlocked-io update-copyright vc-list-files verror 
version-etc version-etc-fsf wait-process xalloc xoset xprintf xvasprintf-posix'

passes as well.

Any hints as to what could make the tests fail when run as part of the M4
git tree and not otherwise?

CC is "cc -qlanglvl=extc89 -qlanglvl=extc99" in both cases, CFLAGS=-g.
LIBOBJS contains strtod.lo respective strtod.o, in both cases
config.status contains these lines:

S["REPLACE_STRTOD"]="1"
S["HAVE_STRTOD"]="1"
S["GNULIB_STRTOD"]="1"
D["HAVE_RAW_DECL_STRTOD"]=" 1"

but in the 'gnulib-tool --test' directories, it also contains

D["HAVE_DECL_STRTOD"]=" 1"

Autoconf on this system was a bit old, 2.62.61-550a5, if you think that
could matter I can retry after updating.

Thanks,
Ralf