autotools & pkg_config: ./autogen.sh fails to find a previously built package

[Frederik Carlier]

Hi,

I'm creating a Snappy package for the libimobiledevice toolset. It consists of a couple of projects which depend on each other, and use pkg-config to detect the presence of the dependencies. 
You can find my .yaml file at https://github.com/quamotion/snappy-arm/blob/master/libimobiledevice/snapcraft.yaml

I'm having an issue building libusbmuxd. libusbmuxd depends on libplist. The ./autogen.sh script will try to detect libplist using pkg-config.
I've updated my .yaml file to make ure libusbmuxd is built after libplist.

At this time, when I build my package using snapcraft build, I get the following error:

> configure: error: Package requirements (libplist >= 1.11) were not met:
> 
> No package 'libplist' found
> 
> Consider adjusting the PKG_CONFIG_PATH environment variable if you
> installed software in a non-standard prefix.
 
I was wondering whether snapcraft is supposed to automatically update the PKG_CONFIG_PATH variable as required, or whether I need to make any changes to my .yaml file to get this to work?

Thanks!

Frederik.