...

No package 'goocanvas' found

Consider adjusting the PKG_CONFIG_PATH environment variable if you
installed software in a non-standard prefix.

Alternatively, you may set the environment variables PACKAGE_CFLAGS
and PACKAGE_LIBS to avoid the need to call pkg-config.
See the pkg-config man page for more details.
==> ERROR: A failure occurred in build().
    Aborting...
==> ERROR: Makepkg was unable to build gpredict.