[Bug libfortran/47802] [4.6 Regression] libgfortran/intrinsics/ctime.c:75:3: error: too few arguments to function 'ctime_r'

["dave at hiauly1 dot hia.nrc.ca" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47802

--- Comment #2 from dave at hiauly1 dot hia.nrc.ca 2011-02-18 20:56:54 UTC ---
> Is there no way to get a posix compliant ctime?  Alternatively, we'll need
> autoconf magic to detect the extra arg.  I know at one time it was relatively
> common, so autoconf magic might be around somewhere.  Assuming it is you just
> have to do something like
> 
> 
> #if defined (oddballctime)
>   *date = ctime_r (&now, cbuf, CSZ);
> #else
>   *date = ctime_r (&now, cbuf);
> #endif

Using ctime_r is a bit of a can of worms.  The GNU autoconf manual recommends
not using ctime_r unless the inputs are known to be within certain limits.

It seems HP-UX and Solaris have both forms.  In the HP-UX 11 case,
which form is used at compilation time depends on _PTHREADS_DRAFT4:

#          ifndef _PTHREADS_DRAFT4
             extern char *ctime_r(const __time_t *, char *);
#          else /* _PTHREADS_DRAFT4 */
         extern int ctime_r(const __time_t *, char *, int);
#          endif /* _PTHREADS_DRAFT4 */

Potential autoconf test:

# ctime_r --
#
# There are two versions of ctime_r, one of which takes a buffer length as a
# third argument, and one which only takes two arguments.  (There is also a
# difference in return values, but we handle that in the code itself.)
AC_CHECK_FUNCS(ctime_r)
if test "$ac_cv_func_ctime_r" = "yes"; then
AC_CACHE_CHECK([for 2 or 3 argument version of ctime_r], db_cv_ctime_r_3arg, [
AC_TRY_LINK([
#include <time.h>], [
    ctime_r(NULL, NULL, 100);
],  [db_cv_ctime_r_3arg="3-argument"], [db_cv_ctime_r_3arg="2-argument"])])
fi
if test "$db_cv_ctime_r_3arg" = "3-argument"; then
    AC_DEFINE(HAVE_CTIME_R_3ARG)
    AH_TEMPLATE(HAVE_CTIME_R_3ARG,
        [Define to 1 if ctime_r takes a buffer length as a third argument.])
fi

Dave