more cleanup

[awesomized/libmemcached] / CMake / CheckVisibility.cmake

diff --git a/CMake/CheckVisibility.cmake b/CMake/CheckVisibility.cmake
new file mode 100644 (file)
index 0000000..91a103a
--- /dev/null
+++ b/CMake/CheckVisibility.cmake
@@ -0,0 +1,22 @@
+configure_define(HAVE_VISIBILITY)
+
+check_flag(-fvisibility=hidden HAVE_VISIBILITY_FLAG)
+if(NOT HAVE_VISIBILITY_FLAG)
+    check_flag(-Wl,-fvisibility=hidden HAVE_VISIBILITY_LINKER_FLAG)
+endif()
+check_c_source("
+        __attribute__ ((visibility (\"default\")))
+        int main(int argc, char **argv) {
+            return *argv[argc-1];
+        }"
+        HAVE_VISIBILITY_ATTR
+)
+
+if(HAVE_VISIBILITY_ATTR AND (HAVE_VISIBILITY_FLAG OR HAVE_VISIBILITY_LINKER_FLAG))
+    if(HAVE_VISIBILITY_LINKER_FLAG)
+        string(APPEND CMAKE_SHARED_LINKER_FLAGS " -Wl,-fvisibility=hidden")
+    else()
+        add_compile_options("-fvisibility=hidden")
+    endif()
+    set(HAVE_VISIBILITY 1 CACHE INTERNAL "-fvisibility and __attribute__((visibility(...)))")
+endif()