Build issue of ps-lite for gflags error

[programming-trgt]

When build ps-lite on Ubuntu 14.04
make -j4
Error appears

/usr/local/lib/libglog.a(libglog_la-utilities.o): In function google::GetStackTrace(void**, int, int)': /home/zixie1991/mygit/ps-lite/glog-0.3.3/src/stacktrace_libunwind-inl.h:65: undefined reference to_Ux86_64_getcontext'
/home/zixie1991/mygit/ps-lite/glog-0.3.3/src/stacktrace_libunwind-inl.h:66: undefined reference to _ULx86_64_init_local' /home/zixie1991/mygit/ps-lite/glog-0.3.3/src/stacktrace_libunwind-inl.h:78: undefined reference to_ULx86_64_step'
/home/zixie1991/mygit/ps-lite/glog-0.3.3/src/stacktrace_libunwind-inl.h:70: undefined reference to `_ULx86_64_get_reg'

[mli]

it's due to you glog is compiled with the libunwind you installed.

please have a pull and then compile with make -j4 EXTRA_LDFLAGS=-lunwind