chore(CI): Reduce the target size when build on GitHub actions (#2086)

The GitHub action runners for free plan is very limit, it's easy to exceed
the disk space.

This patch adds some build and link flags to reduce the target size to ensure
the actions can be completed without disk exhaust issues.

Now the release packge is reduced from about 2,600,468,480 bytes to 686,325,578
bytes, and the ASAN package can be built completly now.

Author: acelyc111

cmake_modules/BaseFunctions.cmake

@@ -193,12 +193,20 @@ endfunction()
 function(dsn_setup_compiler_flags)
   if(CMAKE_BUILD_TYPE STREQUAL "Debug")
     add_definitions(-DDSN_BUILD_TYPE=Debug)
-    add_definitions(-g)
   else()
-    add_definitions(-g)
     add_definitions(-O2)
     add_definitions(-DDSN_BUILD_TYPE=Release)
   endif()
+
+  if("$ENV{GITHUB_ACTION}" STREQUAL "" OR APPLE)
+    add_definitions(-g)
+  else()
+    # Reduce the target size when build on GitHub actions and non-macOS.
+    message(WARNING "Running GitHub actions, the target size will be reduced!")
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Os -ffunction-sections -fdata-sections -fno-unwind-tables -fno-asynchronous-unwind-tables")
+    set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,-s -Wl,--gc-sections")
+  endif()
+
   cmake_host_system_information(RESULT BUILD_HOSTNAME QUERY HOSTNAME)
   add_definitions(-DDSN_BUILD_HOSTNAME=${BUILD_HOSTNAME})