When building x11/gnome-terminal on a powerpc64 the following errors show up: cc -DHAVE_CONFIG_H -I. -I.. -I.. -DTERMINAL_COMPILATION -DTERMINAL_CLIENT -DLOCALEDIR="\"/usr/local/share/locale\"" -DGETTEXT_PACKAGE=\"gnome-terminal\" -isystem /usr/local/include --include config.h -I/usr/local/include/glib-2.0 -I/usr/local/lib/glib-2.0/include -I/usr/local/include -I/usr/local/include/gio-unix-2.0/ -I/usr/local/include/gtk-3.0 -I/usr/local/include/pango-1.0 -I/usr/local/include/cairo -I/usr/local/include/pixman-1 -I/usr/local/include/freetype2 -I/usr/local/include/libdrm -I/usr/local/include/libpng16 -I/usr/local/include/harfbuzz -I/usr/local/include/gdk-pixbuf-2.0 -I/usr/local/include/atk-1.0 -I/usr/local/include/at-spi2-atk/2.0 -I/usr/local/include/at-spi-2.0 -I/usr/local/include/dbus-1.0 -I/usr/local/lib/dbus-1.0/include -I/usr/local/include/dconf -I/usr/local/include/uuid -D_THREAD_SAFE -pthread -Wno-cast-qual -Wno-format-nonliteral -Wno-suggest-attribute=format -Wno-unused-but-set-variable -Wno-unused-function -Wno-unused-variable -Wno-write-strings -O2 -pipe -isystem /usr/local/include -fno-strict-aliasing -MT gterminal-gterminal.o -MD -MP -MF .deps/gterminal-gterminal.Tpo -c -o gterminal-gterminal.o `test -f 'gterminal.c' || echo './'`gterminal.c cc1: error: unrecognized command line option "-Wno-suggest-attribute=format" cc1: error: unrecognized command line option "-Wno-unused-but-set-variable" This could be mitigated by using gcc from ports, or removing those two arguments from the Makefile (via Makefile.am or Makefile.in).
It looks like these options are only used when compiling an uninstalled vala program called 'gterminal'. Since gterminal is never installed into the system, I think we can simply pass '--disable-gterminal' to configure to disable the build of it. gterminal has been removed in GNOME Terminal 3.28.0.
x11/gnome-terminal is at 3.28.2 now, so closing per comment #1.