rafactor: optimize ccache configuration (#64)

Signed-off-by: msclock <[email protected]>

cmake/build/Ccache.cmake

@@ -13,8 +13,12 @@ set(USE_CCACHE
     ON
     CACHE BOOL "use ccache to speed up compiling.")
 
+message(STATUS "Use Ccache with USE_CCACHE: ${USE_CCACHE}
+  Ccache Options:
+    USE_CCACHE: If use ccache to speed up compiling. Default is ON.")
+
 if(NOT USE_CCACHE)
-  message(STATUS "Disable ccache")
+  message(STATUS "Disable ccache because of USE_CCACHE is OFF")
   return()
 endif()
 
@@ -23,14 +27,14 @@ find_program(
   NAMES ccache
   DOC "ccache executable")
 
-if(CCACHE_COMMAND)
-  message(STATUS "Activate ccache: ${CCACHE_COMMAND}")
-  set(CMAKE_C_COMPILER_LAUNCHER "${CCACHE_COMMAND}")
-  set(CMAKE_CXX_COMPILER_LAUNCHER "${CCACHE_COMMAND}")
-
-  # set_property(GLOBAL PROPERTY RULE_LAUNCH_COMPILE ccache)
-
-  # set_property(GLOBAL PROPERTY RULE_LAUNCH_LINK ccache)
-else()
+if(NOT CCACHE_COMMAND)
   message(WARNING "Disable ccache because of no ccache installed")
+  return()
 endif()
+
+set(CMAKE_C_COMPILER_LAUNCHER "${CCACHE_COMMAND}")
+set(CMAKE_CXX_COMPILER_LAUNCHER "${CCACHE_COMMAND}")
+
+# set_property(GLOBAL PROPERTY RULE_LAUNCH_COMPILE ccache)
+
+# set_property(GLOBAL PROPERTY RULE_LAUNCH_LINK ccache)