[...]
Making all in app
gmake[2]: Entering directory `/tmp/gimp-2.0.1/app'
Making all in paint-funcs
gmake[3]: Entering directory `/tmp/gimp-2.0.1/app/paint-funcs'
if gcc -DHAVE_CONFIG_H -I. -I. -I../.. -I../.. -I../../app
-I/usr/local/include/glib-2.0 -I/usr/local/lib/glib-2.0/include  
-I/usr/local/include -DG_LOG_DOMAIN=\"Gimp-Paint-Funcs\" -D_REENTRANT
-DGDK_MULTIHEAD_SAFE -DGTK_MULTIHEAD_SAFE  -s -O3 -march=i686 -Wall -MT
paint-funcs.o -MD -MP -MF ".deps/paint-funcs.Tpo" \
  -c -o paint-funcs.o `test -f 'paint-funcs.c' || echo './'`paint-funcs.c; \
then mv -f ".deps/paint-funcs.Tpo" ".deps/paint-funcs.Po"; \
else rm -f ".deps/paint-funcs.Tpo"; exit 1; \
fi
paint-funcs.c:4484: error: conflicting types for 'initial_region'
paint-funcs.h:359: error: previous declaration of 'initial_region' was here
paint-funcs.c:4484: error: conflicting types for 'initial_region'
paint-funcs.h:359: error: previous declaration of 'initial_region' was here
gmake[3]: *** [paint-funcs.o] Error 1
gmake[3]: Leaving directory `/tmp/gimp-2.0.1/app/paint-funcs'
gmake[2]: *** [all-recursive] Error 1
gmake[2]: Leaving directory `/tmp/gimp-2.0.1/app'
gmake[1]: *** [all-recursive] Error 1
gmake[1]: Leaving directory `/tmp/gimp-2.0.1'
gmake: *** [all] Error 2