While building Go program that requires Gotk3 under Msys2, this error may appear during the build.
go build github.com/gotk3/gotk3/gdk: invalid flag in pkg-config --libs: -Wl,-luuid
Run this command to fix the misconfiguration in the packaged gdk PC file and rebuild.
bash -c "sed -i -e 's/-Wl,-luuid/-luuid/g' /mingw64/lib/pkgconfig/gdk-3.0.pc"
