enh: cmake optimize

contrib/CMakeLists.txt

@@ -230,7 +230,9 @@ endif(${BUILD_WITH_LEVELDB})
 if(${BUILD_WITH_ROCKSDB})
     if(${TD_LINUX})
         SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS_REL} -Wno-error=maybe-uninitialized -Wno-error=unused-but-set-variable -Wno-error=unused-variable -Wno-error=unused-function -Wno-errno=unused-private-field -Wno-error=unused-result")
+        if(NOT ${CMAKE_BUILD_TYPE})
             SET(CMAKE_BUILD_TYPE Release)
+        endif()
     endif(${TD_LINUX})
     MESSAGE(STATUS "CXXXX STATUS CONFIG: " ${CMAKE_CXX_FLAGS})
 
@@ -489,7 +491,9 @@ if(${BUILD_GEOS})
     if(${TD_LINUX})
         set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS_REL}")
         set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS_REL}")
+        if(NOT ${CMAKE_BUILD_TYPE})
             set(CMAKE_BUILD_TYPE Release)
+        endif()
     endif(${TD_LINUX})
     option(BUILD_SHARED_LIBS "Build GEOS with shared libraries" OFF)
     add_subdirectory(geos EXCLUDE_FROM_ALL)