* lib/memcasecmp.c: Include <limits.h>.

* lib/memcasecmp.c: Include <limits.h>.
(memcasecmp): Don't assume UCHAR_MAX <= INT_MAX.
* lib/strtod.c (strtod): Don't assume isspace works on negative chars.
Don't assume isdigit succeeds only on '0' through '9'.

* lib/exclude.c (IN_CTYPE_DOMAIN, is_space): Remove; no longer needed.
All uses of is_space replaced by isspace.
* lib/fnmatch.c (ISASCII): Remove; no longer needed.  All uses removed.
(ISPRINT, ISDIGIT, ISALNUM, ISALPHA, ISCNTRL, ISLOWER, ISPUNCT):
(ISSPACE, ISUPPER, ISXDIGIT): Remove; no longer needed.  All uses
replaced by isprint etc.
* lib/getdate.y (IN_CTYPE_DOMAIN, ISSPACE, ISALPHA, ISLOWER): Likewise.
* lib/getusershell.c (IN_CTYPE_DOMAIN, ISSPACE): Likewise.
* lib/memcasecmp.c (IN_CTYPE_DOMAIN, ISLOWER, TOUPPER): Likewise.
* lib/strtod.c (IN_CTYPE_DOMAIN, ISSPACE, ISDIGIT, TOLOWER): Likewise.
* lib/strtol.c (IN_CTYPE_DOMAIN): Likewise.
* lib/xstrtol.c (IN_CTYPE_DOMAIN, ISSPACE): Likewise.

* m4/xstrtol.m4 (gl_PREREQ_XSTRTOL): Use AC_CHECK_DECLS_ONCE
rather than AC_CHECK_DECLS for strtoimax and strtoumax.
* m4/getusershell.m4 (gl_PREREQ_GETUSERSHELL): Remove; no longer needed.
All uses removed.
* m4/strtol.m4 (gl_PREREQ_STRTOL): Likewise.
* m4/strtoul.m4 (gl_PREREQ_STRTOUL): Likewise.
* m4/exclude.m4 (gl_EXCLUDE): Don't check for isascii; no longer needed.
* m4/getdate.m4 (gl_GETDATE): Likewise.
* m4/getusershell.m4 (gl_PREREQ_GETUSERSHELL): Likewise.
* m4/memcasecmp.m4 (gl_MEMCASECMP): Likewise.
* m4/strtod.m4 (gl_FUNC_STRTOD): Likewise.
* m4/strtol.m4 (gl_PREREQ_STRTOL): Likewise.
* m4/strtoul.m4 (gl_PREREQ_STRTOUL): Likewise.
* m4/xstrtol.m4 (gl_PREREQ_XSTRTOL): Likewise.
* m4/exclude.m4 (gl_EXCLUDE): Don't require AC_C_INLINE; no longer
needed.
* m4/calloc.m4 (_AC_FUNC_CALLOC_IF): Don't require AC_HEADER_STDC;
no longer needed.
* m4/exclude.m4 (gl_EXCLUDE): Likewise.
* m4/getdate.m4 (gl_GETDATE): Likewise.
* m4/getusershell.m4 (gl_PREREQ_GETUSERSHELL): Likewise.
* m4/memcasecmp.m4 (gl_MEMCASECMP): Likewise.
* m4/strtod.m4 (gl_FUNC_STRTOD): Likewise.
* m4/strtol.m4 (gl_PREREQ_STRTOL): Likewise.
* m4/xstrtol.m4 (gl_PREREQ_XSTRTOL): Likewise.