graphics/libcaca build fails on -current i386 (amd64?)

["John D. Baker" <jdbaker%mylinuxisp.com@localhost>]

Building "graphics/libcaca" from pkgsrc-2017Q3 fails on i386 8.99.7 with:

[...]
--- libcaca_la-dither.lo ---
libtool: compile:  gcc -DHAVE_CONFIG_H -I. -I.. -DPLUGINDIR=\"\" -D__LIBCACA__ -I/d0/build/pkgsrc/graphics/libcaca/work/.buildlink/include/ncurses -O2 -D_FORTIFY_SOURCE=2 -g -O2 -fno-strength-reduce -fomit-frame-pointer -Wall -Wpointer-arith -Wcast-align -Wcast-qual -Wstrict-prototypes -Wshadow -Waggregate-return -Wmissing-prototypes -Wnested-externs -Wsign-compare -MT libcaca_la-dither.lo -MD -MP -MF .deps/libcaca_la-dither.Tpo -c dither.c  -fPIC -DPIC -o .libs/libcaca_la-dither.o
dither.c: In function 'caca_dither_bitmap':
dither.c:946:25: warning: variable 'pitch' set but not used [-Wunused-but-set-variable]
     int x1, y1, x2, y2, pitch, deltax, deltay, dchmax;
                         ^
dither.c: In function 'get_rgba_default':
dither.c:1327:16: error: '__BYTE_ORDER' undeclared (first use in this function)
             if(__BYTE_ORDER == __BIG_ENDIAN)
                ^
dither.c:1327:16: note: each undeclared identifier is reported only once for each function it appears in
dither.c:1327:32: error: '__BIG_ENDIAN' undeclared (first use in this function)
             if(__BYTE_ORDER == __BIG_ENDIAN)
                                ^
*** [libcaca_la-dither.lo] Error code 1

make[2]: stopped in /d0/build/pkgsrc/graphics/libcaca/work/libcaca-0.99.beta18/caca


I can't find any place these exact macros are defined.  More curious
yet is that "libcaca" builds just fine on netbsd-8.

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