Re: Unable to find libgif/libungif on RHEL 6

[Wolfgang Jenkner <wjenkner@inode.at>]

On Fri, Sep 11 2015, Kaushal Modi wrote:

> The LDFLAGS did the magic, thank you!

Actually,

./configure ... LDFLAGS=-L/path/to/the/lib64 CPPFLAGS=-I/path/to/gifincludedir

should be enough since configure will add -lgif to LIBS anyway (or do
something else to that effect).

> (I wonder why setting the $LD_LIBRARY_PATH and $PKG_CONFIG_PATH env vars
> did not help.)

LD_LIBRARY_PATH is used at runtime by the dynamic linker ld.so(8),
whereas LDFLAGS belongs to the GNU buildsystem, see

(info "(autoconf) Preset Output Variables").

PKG_CONFIG_PATH is a search path for *.pc files, which giflib doesn't
install (as Paul already mentioned), see pkg-config(1).

There are some (completely untested) variations on the theme:

One could pass

LDFLAGS="-L/path/to/the/lib64 -Wl,-rpath=/path/to/the/lib64"

to configure and so avoid changing LD_LIBRARY_PATH.

Or, if you have the static lib64/libgif.a you could link emacs to it
instead (by simply moving away the lib64/libgif.so* you have in your
home directory before building emacs); in this case, you could even
completely remove the giflib stuff from your home directory after
building emacs.