failure of libGL to compile on 9.2-PRERELEASE

[dacoder at dcoder.net]

i'm having trouble compiling libGL on 9.2-PRERELEASE using portmaster.
firefox requires it.  here's how the compile log file that i created ends:

gmake[3]: Nothing to be done for `default'.
gmake[3]: Leaving directory `/usr/ports/graphics/libGL/work/Mesa-8.0.5/src/mesa/x86'
cc -c -o main/api_exec_es1.o main/api_exec_es1.c -DFEATURE_GL=1 -DHAVE_POSIX_MEMALIGN -DUSE_XCB -DGLX_INDIRECT_RENDERING -DGLX_DIRECT_RENDERING -DPTHREADS -DUSE_EXTERNAL_DXTN_LIB=1 -DIN_DRI_DRIVER -DHAVE_ALIAS -I../../include -I../../src/glsl -I../../src/mesa -I../../src/mapi -I../../src/gallium/include -I../../src/gallium/auxiliary  -I/usr/local/include -O2 -pipe -fno-strict-aliasing -Wall -Wmiss
ing-prototypes -std=c99 -fno-strict-aliasing -fno-builtin-memcmp -O2 -pipe -fno-strict-aliasing -fPIC -DUSE_X86_ASM -DUSE_MMX_ASM -DUSE_3DNOW_ASM -DUSE_SSE_ASM -fvisibility=hidden
python2 -t -O -O ../../src/mapi/glapi/gen/gl_table.py -f ../../src/mapi/glapi/gen/gl_and_es_API.xml -m remap_table -c es2 > main/api_exec_es2_dispatch.h
gmake[2]: Leaving directory `/usr/ports/graphics/libGL/work/Mesa-8.0.5/src/mesa'
gmake[1]: Leaving directory `/usr/ports/graphics/libGL/work/Mesa-8.0.5/src'
*** [do-build] Error code 1

Stop in /usr/ports/graphics/libGL.

i'm not clear exactly what the error is nor, therefore, how to correct it,
nor how to work around it.

suggestions, please.

david coder
dacoder at dcoder.net