in-tree XOrg build failure

[bch <brad.harder%gmail.com@localhost>]

from build attempt:

[...]
dependall ===> external/mit/xorg/server/drivers/xf86-video-ati
dependall ===> external/mit/xorg/server/drivers/xf86-video-intel
#   compile  xf86-video-intel/sna_display.pico
/usr/src/obj/tooldir.NetBSD-7.99.35-amd64/bin/x86_64--netbsd-gcc -O2
-fvisibility=hidden   -std=gnu99   -Werror   -fPIE
-fno-strict-aliasing  --sysroot=/usr/src/obj/destdir.amd64
-I/usr/src/obj/destdir.amd64/usr/X11R7/include/X11
-I/usr/src/obj/destdir.amd64/usr/X11R7/include/X11/dri
-I/usr/src/obj/destdir.amd64/usr/X11R7/include/libdrm
-I/usr/xsrc/external/mit/xf86-video-intel/dist/src
-I/usr/xsrc/external/mit/xf86-video-intel/dist/src/render_program
-I/usr/xsrc/external/mit/xf86-video-intel/dist/xvmc
-DDEFAULT_ACCEL_METHOD=SNA -DENABLE_XVMC=1 -DHAS_PIXMAN_GLYPHS=1
-DHAS_PIXMAN_TRIANGLES=1 -DHAVE_ATOMIC_PRIMITIVES=1 -DHAVE_CPUID_H=1
-DHAVE_DGAPROC_H=1 -DHAVE_DLFCN_H=1 -DHAVE_DRI1=1 -DHAVE_DRI2=1
-DHAVE_DRI2_H=1 -DHAVE_DRISTRUCT_H=1 -DHAVE_DRI_H=1 -DHAVE_GETLINE=1
-DHAVE_INTTYPES_H=1 -DHAVE_MEMORY_H=1 -DHAVE_SAREA_H=1
-DHAVE_STDINT_H=1 -DHAVE_STDLIB_H=1 -DHAVE_STRINGS_H=1
-DHAVE_STRING_H=1 -DHAVE_STRLCAT=1 -DHAVE_STRLCPY=1 -DHAVE_STRNDUP=1
-DHAVE_SYS_IPC_H=1 -DHAVE_SYS_STAT_H=1 -DHAVE_SYS_TYPES_H=1
-DHAVE_UNISTD_H=1 -DHAVE_VGAHW_H=1 -DKMS=1 -DSTDC_HEADERS=1 -DUMS=1
-DUSE_BACKLIGHT=1 -DUSE_SNA=1 -DUSE_UXA=1
-DDRI_DRIVER_PATH=\"/usr/X11R7/lib/modules/dri\"  -DCSRG_BASED
-DFUNCPROTO=15 -DNARROWPROTO
-I/usr/src/obj/destdir.amd64/usr/X11R7/include -D__AMD64__
-I/usr/src/obj/destdir.amd64/usr/X11R7/include/X11
-I/usr/src/obj/destdir.amd64/usr/X11R7/include/X11/dri
-I/usr/src/obj/destdir.amd64/usr/X11R7/include/xorg
-I/usr/src/obj/destdir.amd64/usr/X11R7/include/pixman-1
-I/usr/xsrc/external/mit/xorg-server.old/dist/../include  -DMITMISC
-DXTEST -DXTRAP -DXSYNC -DXCMISC  -DXRECORD -DMITSHM -DBIGREQS
-DXF86VIDMODE  -DXF86MISC -DDPMSExtension -DEVI  -DSCREENSAVER -DXV
-DXVMC -DGLXEXT  -DRES  -DSHAPE -DXINPUT -DXKB -DLBX -DXAPPGROUP
-DXCSECURITY -DTOGCUP -DXF86BIGFONT  -DDPMSExtension -DPIXPRIV
-DPANORAMIX  -DRENDER -DRANDR -DXFIXES -DDAMAGE  -DCOMPOSITE -DXEVIE
-DGLXEXT -DXF86DRI -DGLX_DIRECT_RENDERING  -DGLX_USE_DLOPEN
-DGLX_USE_MESA -DXF86VIDMODE -D__GLX_ALIGN64  -DSHAPE -DXKB -DLBX
-DXAPPGROUP -DXCSECURITY  -DTOGCUP -DXF86BIGFONT -DDPMSExtension
-DPIXPRIV  -DPANORAMIX -DRENDER -DRANDR -DGCCUSESGAS  -DAVOID_GLYPHBLT
-DSINGLEDEPTH -DXvExtension  -DXFree86Server -DXvMCExtension
-DSMART_SCHEDULE  -DBUILDDEBUG -DXResExtension -DNDEBUG -DXINPUT
-DXFreeXDGA -DXF86VIDMODE -DXSERVER_LIBPCIACCESS -D_XSERVER64
-DHAVE_XORG_SERVER_1_1_0  -DSERVER_1_5  -DXSERVER_LIBPCIACCESS
-DHAVE_XEXTPROTO_71 -DHAVE_XAA_H -DXFree86LOADER
-DPACKAGE_VERSION_MAJOR=2 -DPACKAGE_VERSION_MINOR=99
-DPACKAGE_VERSION_PATCHLEVEL=917 -DXORG_VERSION_CURRENT="(((1) *
10000000) + ((10) * 100000) + ((6) * 1000) + 0)" -c
-Wno-stack-protector   -fPIC -g
/usr/xsrc/external/mit/xf86-video-intel/dist/src/sna/sna_display.c -o
sna_display.pico
/usr/xsrc/external/mit/xf86-video-intel/dist/src/sna/sna_display.c: In
function 'sna_cursor_pre_init':
/usr/xsrc/external/mit/xf86-video-intel/dist/src/sna/sna_display.c:5059:0:
error: "DRM_CAP_CURSOR_WIDTH" redefined [-Werror]
 #define DRM_CAP_CURSOR_WIDTH 8
 ^
In file included from
/usr/src/obj/destdir.amd64/usr/X11R7/include/xf86drmMode.h:43:0,
                 from
/usr/xsrc/external/mit/xf86-video-intel/dist/src/sna/sna.h:58,
                 from
/usr/xsrc/external/mit/xf86-video-intel/dist/src/sna/sna_display.c:43:
/usr/src/obj/destdir.amd64/usr/X11R7/include/libdrm/drm.h:636:0: note:
this is the location of the previous definition
 #define DRM_CAP_CURSOR_WIDTH  0x8
 ^
/usr/xsrc/external/mit/xf86-video-intel/dist/src/sna/sna_display.c:5060:0:
error: "DRM_CAP_CURSOR_HEIGHT" redefined [-Werror]
 #define DRM_CAP_CURSOR_HEIGHT 9
 ^
In file included from
/usr/src/obj/destdir.amd64/usr/X11R7/include/xf86drmMode.h:43:0,
                 from
/usr/xsrc/external/mit/xf86-video-intel/dist/src/sna/sna.h:58,
                 from
/usr/xsrc/external/mit/xf86-video-intel/dist/src/sna/sna_display.c:43:
/usr/src/obj/destdir.amd64/usr/X11R7/include/libdrm/drm.h:637:0: note:
this is the location of the previous definition
 #define DRM_CAP_CURSOR_HEIGHT  0x9
 ^
cc1: all warnings being treated as errors
[...]