Re: __GNUC_PREREQ

[Jim Meyering]

Eric Blake wrote:

> According to Eric Blake on 1/28/2010 6:30 AM:
>> because there is no other definition of __GNUC_PREREQ():
>>
>> In file included from ../../lib/regex.c:59:
>> ../../lib/regex_internal.h:854:19: error: missing binary operator before
>> token "("
>>
>> It looks like several other files have a sane definition, such as fts_.h.
>
> For that matter, would it make sense to have a gnulib module that
> guarantees that __GNUC_PREREQ is defined in <config.h>, and then convert
> various other modules to use it rather than open-coding their __GNUC__
> version checks?  On the other hand, modules like string (lib/string.in.h)
> still have to open-code their checks, since the point of replacement
> headers is that they can be installed without <config.h>.

Good idea.
I do see some value in factoring out the duplication (there are
currently 4, and we need a 5th), even if we have to leave a copy
or two open-coded for string.h.