[tex-live] Build of `chktex' for TeXLive SVN trunk fails if one have a `stpcpy' implementation

[Peter Breitenlohner]

On Wed, 10 Oct 2012, Dirk Ullrich wrote:

> Thus I suggest to revert the patch `patch-08-stpcpy' for
> `chktex-1.7.1' and use `configure.in' from `chktex's upstream SVN
> trunk, revision 230, instead: it provides a `stpcpy' implementation
> only if needed via autoconf.

Hi Dirk,

this was discussed with Ivan (the upstream maintainer) before applying that
patch.  Unfortunately things are more complicated.  Our Linux systems also
have the stpcpy() function but do not exhibit a prototype unless one defines
_GNU_SOURCE (for libc < 2.10) resp _XOPEN_SOURCE>=700 or
_POSIX_C_SOURCE>=200809L (for >= 2.10).

Using stpcpy() without previous declaration yields `implicit declaration'
and more warning and possibly bad code, something I'd like to avoid under
all circumstances.  So we need to check if stpcpy is declared in <string.h>
and not only if the function is implemented in the C library.

Regards
Peter Breitenlohner <peb at mppmu.mpg.de>