[build] Enable strip for libtaichi_c_api.so with Release Build

CMakeLists.txt

@@ -6,6 +6,8 @@ cmake_minimum_required(VERSION 3.17)
 
 project(taichi)
 
+include("cmake/utils.cmake")
+
 if (NOT DEFINED TI_VERSION_MAJOR)
     message(WARNING "It seems that you are running cmake manually, which may cause issues. Please use setup.py to build taichi from source, see https://docs.taichi-lang.org/docs/dev_install for more details.")
     set(TI_VERSION_MAJOR 0)
@@ -64,6 +66,8 @@ option(USE_LLD "Use lld (from llvm) linker" OFF)
 option(USE_MOLD "Use mold (A Modern Linker)" OFF)
 option(TI_WITH_BACKTRACE "Use backward-cpp to print out C++ stack trace upon failure" OFF)
 
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -ffunction-sections -fdata-sections")
+
 if (USE_LLD)
     set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -fuse-ld=lld")
     set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} -fuse-ld=lld")

cmake/TaichiCAPI.cmake

@@ -19,9 +19,9 @@ endif()
 
 endfunction()
 
-
 set(TAICHI_C_API_NAME taichi_c_api)
 
+set(TAICHI_C_API_NAME taichi_c_api)
 file(GLOB_RECURSE C_API_SOURCE "c_api/src/taichi_core_impl.cpp")
 
 if (TI_WITH_LLVM)
@@ -49,6 +49,9 @@ endif()
 
 add_library(${TAICHI_C_API_NAME} SHARED ${C_API_SOURCE})
 target_link_static_library(${TAICHI_C_API_NAME} taichi_core)
+target_enable_function_level_linking(${TAICHI_C_API_NAME})
+# Strip shared library
+set_target_properties(${TAICHI_C_API_NAME} PROPERTIES LINK_FLAGS_RELEASE -s)
 
 # Avoid exporting third party symbols from libtaichi_c_api.so
 # Note that on Windows, external symbols will be excluded from .dll automatically, by default.

cmake/utils.cmake

@@ -0,0 +1,7 @@
+function(target_enable_function_level_linking TARGET)
+    if(APPLE)
+        target_link_options(${TARGET} PRIVATE -Wl,-dead_strip)
+    else() # LINUX AND WIN32
+        target_link_options(${TARGET} PRIVATE -Wl,--gc-sections)
+    endif()
+endfunction()