failed to complie webkit-gtk2: Cannot allocate memory

hi all:

i am trying to compile webkit-gtk2 and stuck on error:

===============================================================

ar: warning: can't mmap file: libWebCore_la-SVGFEDisplacementMapElement.o: Cannot allocate memory
ar: warning: can't mmap file: libWebCore_la-SVGFEDropShadowElement.o: Cannot allocate memory
ar: warning: can't mmap file: libWebCore_la-SVGFEFloodElement.o: Cannot allocate memory
[...]
ar: warning: can't mmap file: libWebCore_la-JSNamedNodeMap.o: Cannot allocate memory
ar: warning: can't mmap file: libWebCore_la-JSNavigator.o: Cannot allocate memory
ar: warning: can't mmap file: libWebCore_la-JSNavigatorUserMediaError.o: Cannot allocate memory
ar: warning: can't mmap file: libWebCore_la-JSNavigatorUserMediaErrorCallback.o: Cannot allocate memory
[...]
ar: warning: can't mmap file: libWebCore_la-JSWebSocket.o: Cannot allocate memory
ar: warning: can't mmap file: libWebCore_la-glslang.o: Cannot allocate memory
ar: warning: can't mmap file: libWebCore_la-glslang_tab.o: Cannot allocate memory
ar: warning: can't mmap file: libWebCore_la-JSRequestAnimationFrameCallback.o: Cannot allocate memory
ar: warning: can't mmap file: libWebCore_la-JSHTMLShadowElement.o: Cannot allocate memory
ranlib: fatal: realloc failed: Cannot allocate memory
gmake[1]: *** [libWebCore.la] Error 70
gmake[1]: Leaving directory `/usr/ports/www/webkit-gtk2/work/webkit-1.8.3'
gmake: *** [all] Error 2
===> Compilation failed unexpectedly.
Try to set MAKE_JOBS_UNSAFE=yes and rebuild before reporting the failure to
the maintainer.
*** [do-build] Error code 1

Stop in /usr/ports/www/webkit-gtk2.
*** [build] Error code 1

Stop in /usr/ports/www/webkit-gtk2.
===================================================================


i checked my kernel shared memory and it seem to be pretty big by default:

root_at_giraffe:/usr/ports # sysctl -a | grep -E "shmmax|shmall"
kern.ipc.shmall: 131072
kern.ipc.shmmax: 536870912

thanks help.