From ebc11bc74c4717197df38a037089b656c55a316d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Alexander=20K=C3=B6plinger?= <alex.koeplinger@outlook.com>
Date: Tue, 2 Sep 2025 12:59:05 +0200
Subject: [PATCH] [maccatalyst] Check for -Wno-overriding-option for
 compatibility with clang in Xcode 16.3+

https://github.com/llvm/llvm-project/commit/1c66d08b0137cef7761b8220d3b7cb7833f57cdb renamed the option `-Wno-overriding-t-option` to `-Wno-overriding-option`.
This caused some configure time checks in CMake to fail because of hitting an unknown compiler option.
---
 eng/native/configurecompiler.cmake | 18 +++++++++++++++---
 src/mono/CMakeLists.txt            | 21 +++++++++++++++++++++
 src/mono/mono.proj                 |  2 --
 3 files changed, 36 insertions(+), 5 deletions(-)

diff --git a/eng/native/configurecompiler.cmake b/eng/native/configurecompiler.cmake
index 3c15b9ff389f27..1431234350ae24 100644
--- a/eng/native/configurecompiler.cmake
+++ b/eng/native/configurecompiler.cmake
@@ -676,9 +676,21 @@ if (CLR_CMAKE_HOST_UNIX)
     # a value for mmacosx-version-min (blank CMAKE_OSX_DEPLOYMENT_TARGET gets
     # replaced with a default value, and always gets expanded to an OS version.
     # https://gitlab.kitware.com/cmake/cmake/-/issues/20132
-    # We need to disable the warning that -tagret replaces -mmacosx-version-min
-    set(DISABLE_OVERRIDING_MIN_VERSION_ERROR -Wno-overriding-t-option)
-    add_link_options(-Wno-overriding-t-option)
+    # We need to disable the warning that -target replaces -mmacosx-version-min
+    #
+    # With https://github.com/llvm/llvm-project/commit/1c66d08b0137cef7761b8220d3b7cb7833f57cdb clang renamed the option so we need to check for both
+    check_c_compiler_flag("-Wno-overriding-option" COMPILER_SUPPORTS_W_NO_OVERRIDING_OPTION)
+    if (COMPILER_SUPPORTS_W_NO_OVERRIDING_OPTION)
+      set(DISABLE_OVERRIDING_MIN_VERSION_ERROR -Wno-overriding-option)
+    else()
+      check_c_compiler_flag("-Wno-overriding-t-option" COMPILER_SUPPORTS_W_NO_OVERRIDING_T_OPTION)
+      if (COMPILER_SUPPORTS_W_NO_OVERRIDING_T_OPTION)
+        set(DISABLE_OVERRIDING_MIN_VERSION_ERROR -Wno-overriding-t-option)
+      else()
+        message(FATAL_ERROR "Compiler does not support -Wno-overriding-option or -Wno-overriding-t-option, needed for Mac Catalyst builds.")
+      endif()
+    endif()
+    add_link_options(${DISABLE_OVERRIDING_MIN_VERSION_ERROR})
     if(CLR_CMAKE_HOST_ARCH_ARM64)
       set(CLR_CMAKE_MACCATALYST_COMPILER_TARGET "arm64-apple-ios15.0-macabi")
       add_link_options(-target ${CLR_CMAKE_MACCATALYST_COMPILER_TARGET})
diff --git a/src/mono/CMakeLists.txt b/src/mono/CMakeLists.txt
index b5dc8acebadc7a..38768df87b4adf 100644
--- a/src/mono/CMakeLists.txt
+++ b/src/mono/CMakeLists.txt
@@ -545,6 +545,27 @@ if(GCC)
     set(WARNINGS "${WARNINGS} -Qunused-arguments -Wno-tautological-compare -Wno-parentheses-equality -Wno-self-assign -Wno-return-stack-address -Wno-constant-logical-operand -Wno-zero-length-array -Wno-asm-operand-widths")
   endif()
 
+  if (HOST_MACCAT)
+    # Somewhere between CMake 3.17 and 3.19.4, it became impossible to not pass
+    # a value for mmacosx-version-min (blank CMAKE_OSX_DEPLOYMENT_TARGET gets
+    # replaced with a default value, and always gets expanded to an OS version.
+    # https://gitlab.kitware.com/cmake/cmake/-/issues/20132
+    # We need to disable the warning that -target replaces -mmacosx-version-min
+    #
+    # With https://github.com/llvm/llvm-project/commit/1c66d08b0137cef7761b8220d3b7cb7833f57cdb clang renamed the option so we need to check for both
+    check_c_compiler_flag("-Wno-overriding-option" COMPILER_SUPPORTS_W_NO_OVERRIDING_OPTION)
+    if (COMPILER_SUPPORTS_W_NO_OVERRIDING_OPTION)
+      set(WARNINGS "${WARNINGS} -Wno-overriding-option")
+    else()
+      check_c_compiler_flag("-Wno-overriding-t-option" COMPILER_SUPPORTS_W_NO_OVERRIDING_T_OPTION)
+      if (COMPILER_SUPPORTS_W_NO_OVERRIDING_T_OPTION)
+        set(WARNINGS "${WARNINGS} -Wno-overriding-t-option")
+      else()
+        message(FATAL_ERROR "Compiler does not support -Wno-overriding-option or -Wno-overriding-t-option, needed for Mac Catalyst builds.")
+      endif()
+    endif()
+  endif()
+
   check_c_compiler_flag("-Werror=incompatible-pointer-types" WERROR_INCOMPATIBLE_POINTER_TYPES)
   if(WERROR_INCOMPATIBLE_POINTER_TYPES)
     set(WERROR_C "${WERROR_C} -Werror=incompatible-pointer-types")
diff --git a/src/mono/mono.proj b/src/mono/mono.proj
index 7f79cb409cd3fb..9b3fd3582098bf 100644
--- a/src/mono/mono.proj
+++ b/src/mono/mono.proj
@@ -530,8 +530,6 @@ JS_ENGINES = [NODE_JS]
     <ItemGroup Condition="'$(TargetsMacCatalyst)' == 'true'">
       <_MonoCMakeArgs Include="-DCMAKE_SYSTEM_VARIANT=maccatalyst" />
       <_MonoCMakeArgs Include="-DBUILD_DARWIN_FRAMEWORKS=1" />
-      <!-- https://gitlab.kitware.com/cmake/cmake/-/issues/20132 -->
-      <_MonoCPPFLAGS Include="-Wno-overriding-t-option" />
       <_MonoCFlags Condition="'$(TargetArchitecture)' == 'arm64'" Include="-target arm64-apple-ios$(MacCatalystVersionMin)-macabi" />
       <_MonoCFlags Condition="'$(TargetArchitecture)' == 'x64'" Include="-target x86_64-apple-ios$(MacCatalystVersionMin)-macabi" />
       <_MonoCFLAGS Condition="'$(TargetArchitecture)' == 'arm64'" Include="-arch arm64" />