[squid-dev] [PATCH] search for header files in well-known local directories

[Kinkie]

>> But I believe I found the actual issue, fixed by the attached patch.
>> There's two problems:
>> - headers are checked before PKG_CHECK_MODULES
>> - PKG_CHECK_MODULES sets include-related flags in CFLAGS, but then
>> AC_CHECK_HEADERS uses CPPFLAGS, not CFLAGS.
>
> Arg. Bug in PKG_CHECK_MODULES. It should be setting both.
>
> Maybe we should follow William Pursell's method as outlined in his
> comment to the question
> <http://stackoverflow.com/questions/10220946/pkg-check-modules-considered-harmful>.

It's messy, need to un-cache values to make it work :(
Let's not fix a problem which is not yet apparent; let's keep the
reference around if it gets bad, but until then let's KIS.

>> The patch addresses both by:
>> - calling PKG_CHECK_MODULES before AC_CHECK_HEADERS
>> - extending SQUID_STATE_* macros to also cover CPPFLAGS
>> - manually setting CPPFLAGS for the benefit of AC_CHECK_HEADERS (and
>> rolling it back once the check is done).
>>
>
> +1 on this new patch.

committed as 14476.

> Also need to check and fix the OpenSSL use of PKG_CHECK_MODULES which is
> probably suffering in the same way.

On MacOS openssl stuff is in /usr/include/openssl and /usr/lib; I have
no way to check.

> The krb5 libraries might be too, but do not use AC_CHECK_HEADERS in the
> same way.

Kerberos librararies are way messy. Kudos to Markus for being able to
navigate through that.

-- 
    Francesco