[...]
Making all in papi
make[4]: Entering directory `/tmp/gtk+-2.18.3/modules/printbackends/papi'
/bin/sh ../../../libtool  --tag=CC   --mode=compile gcc -DHAVE_CONFIG_H -I. -I../../.. -I../../.. -I../../../gtk -I../../../gtk -I../../../gdk -I../../../gdk -DGTK_PRINT_BACKEND_ENABLE_UNSUPPORTED -pthread -I/usr/local/include/glib-2.0 -I/usr/local/lib/glib-2.0/include -I/usr/local/include/pango-1.0 -I/usr/local/include/cairo -I/usr/local/include/atk-1.0 -I/usr/local/include/freetype2 -I/usr/local/include      -DG_DISABLE_ASSERT -DG_DISABLE_CHECKS -DG_DISABLE_CAST_CHECKS  -DG_DISABLE_SINGLE_INCLUDES -DATK_DISABLE_SINGLE_INCLUDES -DGDK_PIXBUF_DISABLE_SINGLE_INCLUDES -DGTK_DISABLE_SINGLE_INCLUDES -I/usr/local/include    -DGDK_PIXBUF_DISABLE_DEPRECATED -s -O3 -march=i686 -Wall -MT gtkprintbackendpapi.lo -MD -MP -MF .deps/gtkprintbackendpapi.Tpo -c -o gtkprintbackendpapi.lo gtkprintbackendpapi.c
libtool: compile:  gcc -DHAVE_CONFIG_H -I. -I../../.. -I../../.. -I../../../gtk -I../../../gtk -I../../../gdk -I../../../gdk -DGTK_PRINT_BACKEND_ENABLE_UNSUPPORTED -pthread -I/usr/local/include/glib-2.0 -I/usr/local/lib/glib-2.0/include -I/usr/local/include/pango-1.0 -I/usr/local/include/cairo -I/usr/local/include/atk-1.0 -I/usr/local/include/freetype2 -I/usr/local/include -DG_DISABLE_ASSERT -DG_DISABLE_CHECKS -DG_DISABLE_CAST_CHECKS -DG_DISABLE_SINGLE_INCLUDES -DATK_DISABLE_SINGLE_INCLUDES -DGDK_PIXBUF_DISABLE_SINGLE_INCLUDES -DGTK_DISABLE_SINGLE_INCLUDES -I/usr/local/include -DGDK_PIXBUF_DISABLE_DEPRECATED -s -O3 -march=i686 -Wall -MT gtkprintbackendpapi.lo -MD -MP -MF .deps/gtkprintbackendpapi.Tpo -c gtkprintbackendpapi.c  -fPIC -DPIC -o .libs/gtkprintbackendpapi.o
gtkprintbackendpapi.c: In function 'gtk_print_backend_papi_print_stream':
gtkprintbackendpapi.c:355: error: incompatible types when initializing type 'papi_status_t' using type 'void *'
gtkprintbackendpapi.c:351: warning: unused variable 'argv'
gtkprintbackendpapi.c:350: warning: unused variable 'in_fd'
gtkprintbackendpapi.c:349: warning: unused variable 'argc'
gtkprintbackendpapi.c:345: warning: unused variable 'print_error'
gtkprintbackendpapi.c: In function 'papi_get_printer_list':
gtkprintbackendpapi.c:582: warning: unused variable 'attrs'
gtkprintbackendpapi.c:581: warning: unused variable 'url'
gtkprintbackendpapi.c:581: warning: unused variable 'name'
gtkprintbackendpapi.c:560: warning: unused variable 'current_printer_list'
gtkprintbackendpapi.c:558: warning: unused variable 'printer'
gtkprintbackendpapi.c:555: warning: unused variable 'status2'
gtkprintbackendpapi.c:549: warning: unused variable 'attributes'
gtkprintbackendpapi.c: In function 'update_printer_status':
gtkprintbackendpapi.c:647: warning: unused variable 'status_changed'
gtkprintbackendpapi.c: In function 'papi_printer_get_options':
gtkprintbackendpapi.c:667: warning: unused variable 'i'
gtkprintbackendpapi.c: In function 'papi_printer_prepare_for_print':
gtkprintbackendpapi.c:746: warning: assignment discards qualifiers from pointer target type
gtkprintbackendpapi.c: In function 'merge_ppd_data':
gtkprintbackendpapi.c:772: warning: implicit declaration of function 'get_ppd_attrs'
gtkprintbackendpapi.c: In function 'papi_display_printer_status':
gtkprintbackendpapi.c:800: warning: unused variable 'count'
gtkprintbackendpapi.c:795: warning: unused variable 'ppdfile'
gtkprintbackendpapi.c:795: warning: unused variable 'printer_uri'
make[4]: *** [gtkprintbackendpapi.lo] Error 1
make[4]: Leaving directory `/tmp/gtk+-2.18.3/modules/printbackends/papi'
make[3]: *** [all-recursive] Error 1
make[3]: Leaving directory `/tmp/gtk+-2.18.3/modules/printbackends'
make[2]: *** [all-recursive] Error 1
make[2]: Leaving directory `/tmp/gtk+-2.18.3/modules'
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/tmp/gtk+-2.18.3'
make: *** [all] Error 2