including ./system/extras/Android.mk ...
including ./system/keymaster/Android.mk ...
including ./system/media/audio_route/Android.mk ...
including ./system/media/audio_utils/Android.mk ...
including ./system/media/camera/src/Android.mk ...
including ./system/media/camera/tests/Android.mk ...
including ./system/netd/client/Android.mk ...
including ./system/netd/server/Android.mk ...
including ./system/security/keystore-engine/Android.mk ...
including ./system/security/keystore/Android.mk ...
including ./system/security/softkeymaster/Android.mk ...
including ./system/vold/Android.mk ...
including ./tools/external/fat32lib/Android.mk ...
host C++: libnativehelper_32 <= libnativehelper/JNIHelp.cpp
libnativehelper/JNIHelp.cpp:28:10: fatal error: 'string' file not found
#include <string>
^
1 error generated.
make: *** [out/host/darwin-x86/obj32/SHARED_LIBRARIES/libnativehelper_intermediates/JNIHelp.o] Error 1
#### make failed to build some targets (01:10 (mm:ss)) ####
it cannot find the <string> head ,does anyone how to solve this problem ??? thx!!!!!