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RE: Curl Configuration Weirdness for libz.a

From: Randall via curl-library <>
Date: Thu, 31 Aug 2023 10:49:12 -0400

On Wednesday, August 30, 2023 7:43 PM, Fandrich wrote:
>On Wed, Aug 30, 2023 at 06:08:38PM -0400, wrote:
>> Unfortunately, the packaging team for the platform did not help on this
one. zlib.h
>is in the /usr/coreutils/include directory, the zlib.a,, are in
>/usr/coreutils/lib (which collide). The zlib.pc file does not help
>> prefix=/usr/coreutils
>> exec_prefix=${prefix}
>> libdir=${exec_prefix}/lib
>> sharedlibdir=${libdir}
>> includedir=${prefix}/include
>> Name: zlib
>> Description: zlib compression library
>> Version: 1.2.11
>> Requires:
>> Libs: -L${libdir} -L${sharedlibdir} -lz
>> Cflags: -I${includedir}
>You could try hacking a copy of zlib.pc and replace "-lz" with
>then force configure to use it with PKG_CONFIG_PATH=/path/to/hacked/file,
but I'm
>pretty sure that even that won't completely get rid of the use of -lz.
>Running 'make ZLIB_LIBS=' after the configure should get rid of one
>instance of it but there's another one that will still show up.
>If you can confirm that behaviour, then IMHO, configure should be changed
to stop
>doing that. If pkg-config has successfully found zlib, then configure
shouldn't be
>adding its own libraries and link flags to what pkg-config says is correct.

When using a modified zlib.pc, the warning goes away, but -lz is added back
by configure. The zlib.a is ignored, which is not the desired outcome. My
zlib.pc as the Libs: line modified as follows (libz.a has to come first but
does not take effect this way):

Libs: ${libdir}/libz.a -L${libdir} -L${sharedlibdir}

Instead of the original

Libs: -L${libdir} -L${sharedlibdir} -lz

Using make ZLIB_LIBS=/usr/coreutils/lib/libz.a does not change the behaviour
from the original post. I'm not sure this is the confirmation you are
looking for.

>> which really will force being selected, and I cannot use
that for
>packaging curl for the general population as that DLL is only available on
>minority of machines. (On that subject, can you change the ref on
> from my name to ITUGLIB - which is the
volunteer org
>who would take over if I get hit by a bus - but I'm glad we're listed there
and it is
>otherwise correct).

Received on 2023-08-31