From 2cc3720a573e982c20a0f01f8db4dd8efe4f31c0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tor=20Arne=20Vestb=C3=B8?= <tor.arne.vestbo@qt.io>
Date: Mon, 23 Sep 2019 13:35:06 +0200
Subject: [PATCH] macOS: Prevent warnings about object files without any
 symbols

Change-Id: I0860b95cd75f536ff20defde97c3df7dc78a1e18
Reviewed-by: Qt CMake Build Bot
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>
---
 cmake/QtBuild.cmake | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/cmake/QtBuild.cmake b/cmake/QtBuild.cmake
index 4ddbcff3ab..8f249a15fe 100644
--- a/cmake/QtBuild.cmake
+++ b/cmake/QtBuild.cmake
@@ -231,6 +231,18 @@ set(QT_BUILD_INTERNALS_EXTRA_CMAKE_CODE "")
 # This will be /path/to/qtbase/tests when building standalone tests.
 set(QT_TOP_LEVEL_SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}")
 
+# Prevent warnings about object files without any symbols. This is a common
+# thing in Qt as we tend to build files unconditionally, and then use ifdefs
+# to compile out parts that are not relevant.
+if(CMAKE_HOST_APPLE AND APPLE)
+    foreach(lang ASM C CXX)
+        # We have to tell 'ar' to not run ranlib by itself, by passing the 'S' option
+        set(CMAKE_${lang}_ARCHIVE_CREATE "<CMAKE_AR> qcS <TARGET> <LINK_FLAGS> <OBJECTS>")
+        set(CMAKE_${lang}_ARCHIVE_APPEND "<CMAKE_AR> qS <TARGET> <LINK_FLAGS> <OBJECTS>")
+        set(CMAKE_${lang}_ARCHIVE_FINISH "<CMAKE_RANLIB> -no_warning_for_no_symbols <TARGET>")
+    endforeach()
+endif()
+
 # Functions and macros:
 
 # qt_remove_args can remove arguments from an existing list of function