From 66b7cb2a88a0cb1251f1d7c39231ab1e8a35b470 Mon Sep 17 00:00:00 2001
From: Amir Masoud Abdol <amir.abdol@qt.io>
Date: Mon, 16 Oct 2023 11:24:38 +0200
Subject: [PATCH] Suppress "duplicate libraries" warning for Xcode 15
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A bug in Xcode 15 adds duplicate flags to the linker. In addition, the
`-warn_duplicate_libraries` is now enabled by default which may result
in several 'duplicate libraries warning', and build failure if
`-Wl,-fatal_warnings` is passed. By adding the newly introduced
flag, `-no_warn_duplicate_libraries`, to the linker we can suppress the
warnings, and possible fatal error caused by this bug.

Change-Id: I65e06ea039a6e98b02ed1f9112c622ecc6a142b5
Reviewed-by: Alexey Edelev <alexey.edelev@qt.io>
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>
---
 cmake/QtInternalTargets.cmake | 35 ++++++++++++++++++++++-------------
 1 file changed, 22 insertions(+), 13 deletions(-)

diff --git a/cmake/QtInternalTargets.cmake b/cmake/QtInternalTargets.cmake
index 52ba63c762..29e3483c71 100644
--- a/cmake/QtInternalTargets.cmake
+++ b/cmake/QtInternalTargets.cmake
@@ -229,19 +229,28 @@ elseif(UIKIT)
     target_compile_definitions(PlatformCommonInternal INTERFACE GLES_SILENCE_DEPRECATION)
 endif()
 
-if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "AppleClang"
-    AND CMAKE_CXX_COMPILER_VERSION VERSION_GREATER_EQUAL "14.0.0"
-)
-    # Xcode 14's Clang will emit objc_msgSend stubs by default, which ld
-    # from earlier Xcode versions will fail to understand when linking
-    # against static libraries with these stubs. Disable the stubs explicitly,
-    # for as long as we do support Xcode < 14.
-    set(is_static_lib "$<STREQUAL:$<TARGET_PROPERTY:TYPE>,STATIC_LIBRARY>")
-    set(is_objc "$<COMPILE_LANGUAGE:OBJC,OBJCXX>")
-    set(is_static_and_objc "$<AND:${is_static_lib},${is_objc}>")
-    target_compile_options(PlatformCommonInternal INTERFACE
-        "$<${is_static_and_objc}:-fno-objc-msgsend-selector-stubs>"
-    )
+if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "AppleClang")
+    if(CMAKE_CXX_COMPILER_VERSION VERSION_GREATER_EQUAL "14.0.0")
+        # Xcode 14's Clang will emit objc_msgSend stubs by default, which ld
+        # from earlier Xcode versions will fail to understand when linking
+        # against static libraries with these stubs. Disable the stubs explicitly,
+        # for as long as we do support Xcode < 14.
+        set(is_static_lib "$<STREQUAL:$<TARGET_PROPERTY:TYPE>,STATIC_LIBRARY>")
+        set(is_objc "$<COMPILE_LANGUAGE:OBJC,OBJCXX>")
+        set(is_static_and_objc "$<AND:${is_static_lib},${is_objc}>")
+        target_compile_options(PlatformCommonInternal INTERFACE
+            "$<${is_static_and_objc}:-fno-objc-msgsend-selector-stubs>"
+        )
+    endif()
+    if(CMAKE_CXX_COMPILER_VERSION VERSION_GREATER_EQUAL "15.0.0")
+        # A bug in Xcode 15 adds duplicate flags to the linker. In addition, the
+        # `-warn_duplicate_libraries` is now enabled by default which may result
+        # in several 'duplicate libraries warning'.
+        #   - https://gitlab.kitware.com/cmake/cmake/-/issues/25297 and
+        #   - https://indiestack.com/2023/10/xcode-15-duplicate-library-linker-warnings/
+        target_link_options(PlatformCommonInternal INTERFACE
+            "LINKER:-no_warn_duplicate_libraries")
+    endif()
 endif()
 
 if(MSVC)