diff --git a/code/CMakeModules/PCHSupport.cmake b/code/CMakeModules/PCHSupport.cmake
index 36d031f10..c396bd6cf 100644
--- a/code/CMakeModules/PCHSupport.cmake
+++ b/code/CMakeModules/PCHSupport.cmake
@@ -114,12 +114,16 @@ MACRO(PCH_SET_COMPILE_FLAGS _target)
 
   GET_TARGET_PROPERTY(oldProps ${_target} COMPILE_FLAGS)
   IF(oldProps)
-    LIST(APPEND _FLAGS ${oldProps})
+    SET(_FLAG ${oldProps})
+    SEPARATE_ARGUMENTS(_FLAG)
+    LIST(APPEND _FLAGS ${_FLAG})
   ENDIF()
 
   GET_TARGET_PROPERTY(oldPropsBuild ${_target} COMPILE_FLAGS_${_UPPER_BUILD})
   IF(oldPropsBuild)
-    LIST(APPEND _FLAGS ${oldPropsBuild})
+    SET(_FLAG ${oldPropsBuild})
+    SEPARATE_ARGUMENTS(_FLAG)
+    LIST(APPEND _FLAGS ${_FLAG})
   ENDIF()
 
   GET_TARGET_PROPERTY(DIRINC ${_target} INCLUDE_DIRECTORIES)
@@ -205,6 +209,10 @@ MACRO(PCH_SET_COMPILE_FLAGS _target)
     ENDIF()
   ENDIF()
 
+  IF(USE_CPP0X AND gcc_compiler_version GREATER "6.2.0")
+    LIST(APPEND _FLAGS "-std=gnu++11")
+  ENDIF()
+
   # Format definitions
   IF(MSVC)
     # Fix path with space
@@ -316,7 +324,7 @@ MACRO(PCH_SET_COMPILE_COMMAND _inputcpp _compile_FLAGS)
     SET(_FLAGS "")
     IF(APPLE)
       SET(HEADER_FORMAT "objective-${HEADER_FORMAT}")
-      SET(_FLAGS -fobjc-abi-version=2 -fobjc-legacy-dispatch)
+      SET(_FLAGS ${OBJC_FLAGS})
     ENDIF()
     SET(PCH_COMMAND ${CMAKE_CXX_COMPILER} ${pchsupport_compiler_cxx_arg1} ${_compile_FLAGS} ${_FLAGS} -x ${HEADER_FORMAT} -o ${PCH_OUTPUT} -c ${PCH_INPUT})
   ENDIF()
@@ -402,7 +410,8 @@ MACRO(ADD_PRECOMPILED_HEADER_TO_TARGET _targetName)
     ENDIF()
 
     IF(APPLE)
-      SET(PCH_ADDITIONAL_COMPILER_FLAGS "-fobjc-abi-version=2 -fobjc-legacy-dispatch -x objective-c++ ${PCH_ADDITIONAL_COMPILER_FLAGS}")
+      STRING(REPLACE ";" " " OBJC_FLAGS_STR "${OBJC_FLAGS}")
+      SET(PCH_ADDITIONAL_COMPILER_FLAGS "${OBJC_FLAGS_STR} -x objective-c++ ${PCH_ADDITIONAL_COMPILER_FLAGS}")
     ENDIF()
 
     IF(WITH_PCH_DEBUG)
diff --git a/code/CMakeModules/nel.cmake b/code/CMakeModules/nel.cmake
index a8879fd4d..95b28bb8a 100644
--- a/code/CMakeModules/nel.cmake
+++ b/code/CMakeModules/nel.cmake
@@ -565,8 +565,8 @@ MACRO(NL_SETUP_BUILD)
     ADD_PLATFORM_FLAGS("/X")
 
     IF(MSVC14)
-      ADD_PLATFORM_FLAGS("/Gy- /MP")
-      # /Ox is working with VC++ 2015, but custom optimizations don't exist
+      ADD_PLATFORM_FLAGS("/Gy-")
+      # /Ox is working with VC++ 2015 and 2017, but custom optimizations don't exist
       SET(RELEASE_CFLAGS "/Ox /GF /GS- ${RELEASE_CFLAGS}")
       # without inlining it's unusable, use custom optimizations again
       SET(DEBUG_CFLAGS "/Od /Ob1 /GF- ${DEBUG_CFLAGS}")
@@ -664,6 +664,8 @@ MACRO(NL_SETUP_BUILD)
     ENDIF()
 
     IF(APPLE)
+      SET(OBJC_FLAGS -fobjc-abi-version=2 -fobjc-legacy-dispatch -fobjc-weak)
+    
       IF(NOT XCODE)
         IF(CMAKE_OSX_ARCHITECTURES)
           SET(TARGETS_COUNT 0)
@@ -1167,6 +1169,7 @@ MACRO(SETUP_EXTERNAL)
 
     IF(APPLE)
       IF(WITH_STATIC_EXTERNAL)
+        # Look only for static libraries because systems libraries are using Frameworks
         SET(CMAKE_FIND_LIBRARY_SUFFIXES .a)
       ELSE()
         SET(CMAKE_FIND_LIBRARY_SUFFIXES .dylib .so .a)
@@ -1180,12 +1183,13 @@ MACRO(SETUP_EXTERNAL)
     ENDIF()
   ENDIF()
 
-  # Android and iOS have pthread
-  IF(ANDROID OR IOS)
+  # Android, iOS and Mac OS X have pthread, but no need to link to libpthread
+  IF(ANDROID OR APPLE)
     SET(CMAKE_USE_PTHREADS_INIT 1)
     SET(Threads_FOUND TRUE)
   ELSE()
-    FIND_PACKAGE(Threads REQUIRED)
+    SET(THREADS_HAVE_PTHREAD_ARG ON)
+    FIND_PACKAGE(Threads)
     # TODO: replace all -l<lib> by absolute path to <lib> in CMAKE_THREAD_LIBS_INIT
   ENDIF()
 
diff --git a/code/ryzom/client/src/CMakeLists.txt b/code/ryzom/client/src/CMakeLists.txt
index 26b208c67..f0409a2e1 100644
--- a/code/ryzom/client/src/CMakeLists.txt
+++ b/code/ryzom/client/src/CMakeLists.txt
@@ -177,7 +177,6 @@ IF(WITH_RYZOM_CLIENT)
               ${LUA_LIBRARIES}
               ${LUABIND_LIBRARIES}
               ${CURL_LIBRARIES}
-              ${OPENSSL_LIBRARIES}
   )
 
   IF(NOT APPLE AND NOT WIN32)