Setup $PKG_CONFIG_PATH' in /etc/profile'.

svn path=/nixos/trunk/; revision=10971

etc/profile.sh

@@ -55,6 +55,7 @@ NIX_PROFILES="/nix/var/nix/profiles/default $NIX_USER_PROFILE_DIR/profile"
 for i in $NIX_PROFILES; do # !!! reverse
     export PATH=$i/bin:$i/sbin:$PATH
     export INFOPATH=$i/info:$i/share/info:$INFOPATH
+    export PKG_CONFIG_PATH="$i/lib/pkgconfig:$PKG_CONFIG_PATH"
 done
 
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