fix some compile problem like

CMakeLists.txt

@@ -202,7 +202,11 @@ include_directories(
         ${OPENSSL_INCLUDE_DIR}
         )
 
+set(WL_START_GROUP "-Wl,--start-group")
+set(WL_END_GROUP "-Wl,--end-group")
+
 set(DYNAMIC_LIB
+    ${WL_START_GROUP}
     ${GFLAGS_LIBRARY}
     ${PROTOBUF_LIBRARIES}
     ${LEVELDB_LIB}
@@ -220,7 +224,7 @@ else()
     list(APPEND DYNAMIC_LIB ${OPENSSL_SSL_LIBRARY})
 endif()
 
-set(BRPC_PRIVATE_LIBS "-lgflags -lprotobuf -lleveldb -lprotoc -lssl -lcrypto -ldl -lz")
+set(BRPC_PRIVATE_LIBS  ${WL_START_GROUP} "-lgflags -lprotobuf -lleveldb -lprotoc -lssl -lcrypto -ldl -lz")
 
 if(WITH_GLOG)
     set(DYNAMIC_LIB ${DYNAMIC_LIB} ${GLOG_LIB})
@@ -249,6 +253,9 @@ elseif(CMAKE_SYSTEM_NAME STREQUAL "Darwin")
         "-Wl,-U,_ProfilerStop")
 endif()
 
+set(DYNAMIC_LIB "${DYNAMIC_LIB} ${WL_END_GROUP}")
+set(BRPC_PRIVATE_LIBS "${BRPC_PRIVATE_LIBS} ${WL_END_GROUP}")
+
 # for *.so
 set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${PROJECT_BINARY_DIR}/output/lib)
 # for *.a