Add linker version script to explicitly expose symbols. Refs #683

* When statically linking libstdc++ by default the symbols are all
  default visibility. This causes a problem if you statically link an
  old libstdc++ then inject librenderdoc.so, and the application starts
  using the old libstdc++ instead of the system's.
* Really we only want to use the static one for calls from
  librenderdoc.so. In theory -Wl,--exclude-libs,libstdc++ should do this
  for us, but it starts to cause bizarre crashes.
* Instead, we have to resort to a manual linker script which whitelists
  which symbols should be visible. Normally we can do this just for our
  own symbols with -fvisibility=hidden and __attribute__((visibility))
  but that doesn't work for linked symbols apparently.

renderdoc/CMakeLists.txt

@@ -307,6 +307,10 @@ target_compile_definitions(renderdoc ${RDOC_DEFINITIONS})
 target_include_directories(renderdoc ${RDOC_INCLUDES})
 target_link_libraries(renderdoc ${RDOC_LIBRARIES})
 
+if(UNIX AND NOT ANDROID)
+    set_target_properties(renderdoc PROPERTIES LINK_FLAGS "-Wl,--version-script,${CMAKE_CURRENT_SOURCE_DIR}/renderdoc.version")
+endif()
+
 install (TARGETS renderdoc DESTINATION lib${LIB_SUFFIX})
 
 # Copy in application API header to include

renderdoc/renderdoc.version

@@ -0,0 +1,12 @@
+{
+        global:
+                _init;
+                _fini;
+                gl[A-Z]*;
+                dlopen;
+                _exit;
+                RENDERDOC_*;
+                VK_LAYER_RENDERDOC_*;
+        local:
+                *;
+};