Multiple definition error using GFLAGS with tcmalloc

Question

~/common/lib/libglog.a(libglog_la-utilities.o): In function `google::LogMessageVoidify::LogMessageVoidify()':
~/glog/glog-0.3.2/src/utilities.cc:80: multiple definition of `FLAG__namespace_do_not_use_directly_use_DECLARE_bool_instead::FLAGS_symbolize_stacktrace'
~/common/lib/libtcmalloc.a(libtcmalloc_minimal_debug_la-debugallocation.o):~/tcmalloc/optimized/gperftools-r218/src/libc_override_glibc.h:100: first defined here

Getting above mentioned error while doing code coverage for project code. Without code coverage its compiling, but not with code coverage. Code coverage library used is -lgcov.