How do you specify the pkg-config path when compiling something with cmake?

I want to build ffmpeg with support for the av1 codec on CentOS 7. I start by following the instructions here : git clone https://aomedia.googlesource.com/aom mkdir aom_build cd aom_build cmake ../aom make sudo make install This writes a file to /usr/local/lib64/pkgconfig/aom.pc. When I later clone ffmpeg's git repo and try to run ./configure --enable-libaom ..., it complains that pkg-config can't find the aom.pc file. This is because if I run pkg-config --variable pc_path pkg-config, I can see that pkg-config only checks here: /usr/lib64/pkgconfig:/usr/share/pkgconfig It doesn't look in /usr/local/lib64/pkgconfig, where aom.pc is. So far, the only fix I've come up with is to run this instead in ffmpeg's git directory: PKG_CONFIG_PATH=$PKG_CONFIG_PATH/usr/local/lib64/pkgconfig: ./configure --enable-libaom ... This works, but I'd rather just tell libaom to write aom.pc to /usr/lib64/pkgconfig in the first place. Is there any way, when building aom, to tell cmake or make to write the aom.pc file to /usr/lib64/pkgconfig instead of /usr/local/lib64/pkgconfig? In other projects that have a ./configure step, I've seen it possible to specify this with ./configure --pkgconfigdir=/usr/lib64/pkgconfig, but the aom project doesn't have a ./configure script, so I'm not sure what to do here.