[BUILD] Enable more visible symbols by default (#3365)

CMakeLists.txt

@@ -37,6 +37,7 @@ tvm_option(USE_SGX "Build with SGX" OFF)
 tvm_option(USE_RTTI "Build with RTTI" ON)
 tvm_option(USE_MSVC_MT "Build with MT" OFF)
 tvm_option(INSTALL_DEV "Install compiler infrastructure" OFF)
+tvm_option(HIDE_PRIVATE_SYMBOLS "Compile with -fvisibility=hidden." OFF)
 
 # 3rdparty libraries
 tvm_option(DLPACK_PATH "Path to DLPACK" "3rdparty/dlpack/include")
@@ -96,8 +97,13 @@ else(MSVC)
     set(CMAKE_C_FLAGS "-O0 -g -Wall -fPIC ${CMAKE_C_FLAGS} -rdynamic")
     set(CMAKE_CXX_FLAGS "-O0 -g -Wall -fPIC -std=c++11 ${CMAKE_CXX_FLAGS} -rdynamic")
   else()
-    set(CMAKE_C_FLAGS "-O2 -Wall -fPIC -fvisibility=hidden ${CMAKE_C_FLAGS}")
-    set(CMAKE_CXX_FLAGS "-O2 -Wall -fPIC -fvisibility=hidden -std=c++11 ${CMAKE_CXX_FLAGS}")
+    set(CMAKE_C_FLAGS "-O2 -Wall -fPIC ${CMAKE_C_FLAGS}")
+    set(CMAKE_CXX_FLAGS "-O2 -Wall -fPIC -std=c++11 ${CMAKE_CXX_FLAGS}")
+    if (HIDE_PRIVATE_SYMBOLS)
+      message("Hide private symbols...")
+      set(CMAKE_C_FLAGS "-fvisibility=hidden ${CMAKE_C_FLAGS}")
+      set(CMAKE_CXX_FLAGS "-fvisibility=hidden ${CMAKE_CXX_FLAGS}")
+    endif(HIDE_PRIVATE_SYMBOLS)
   endif ()
   if (CMAKE_CXX_COMPILER_ID MATCHES "GNU" AND
       CMAKE_CXX_COMPILER_VERSION VERSION_GREATER 7.0)

Jenkinsfile

@@ -185,6 +185,7 @@ stage('Build') {
            echo set\\(USE_ANTLR ON\\) >> config.cmake
            echo set\\(CMAKE_CXX_COMPILER g++\\) >> config.cmake
            echo set\\(CMAKE_CXX_FLAGS -Werror\\) >> config.cmake
+           echo set\\(HIDE_PRIVATE_SYMBOLS ON\\) >> config.cmake
            """
         make(ci_cpu, 'build', '-j2')
         pack_lib('cpu', tvm_lib)