Introduce macOS toolchain setup for CMake

igormunkin · igormunkin · commit b17c2b69e99d · 2024-12-01T19:24:54.000+03:00
It was mentioned in the commit 89ac4bf ("Upgrade to macOS 12 in GitHub Actions"), macos-13 runners use Clang 15 compiler toolchain, that requires to tweak compiler flags the same way it was done in the commit 3ac8f71 ("Suppress -Wgnu-null-pointer-arithmetics for Clang"). At the same time, we only support the one version on macOS (unlike Linux distributions), so the compiler to be used is well-defined. Taking into account all of the above, this patch introduces the new CMake toolchain file with a tiny tweak (and a huge reasoning for it) to make AppleClang happy on macOS-13. There are no other issues found by the upgrade, but the whole macOS pipeline still should be refined. Follows up #63 Signed-off-by: Igor Munkin <imun@cpan.org>
diff --git a/.github/workflows/macos.yml b/.github/workflows/macos.yml
@@ -62,3 +62,4 @@ jobs:
         uses: ./.github/actions/run-tests
         with:
           cmakeflags: ${{ matrix.CMAKEFLAGS }}
+          toolchain: cmake/toolchain/MacOS.cmake
diff --git a/cmake/toolchain/MacOS.cmake b/cmake/toolchain/MacOS.cmake
@@ -0,0 +1,21 @@
+# MacOS toolchain for building uJIT. To enable, run cmake like this:
+#
+# $ cmake -DCMAKE_TOOLCHAIN_FILE=cmake/toolchain/MacOS.cmake ...other options...
+#
+# Copyright (C) 2020-2024 LuaVela Authors. See Copyright Notice in COPYRIGHT
+# Copyright (C) 2015-2020 IPONWEB Ltd. See Copyright Notice in COPYRIGHT
+
+# XXX: Clang 15 changes the behaviour of -Wnull-pointer-arithmetics to control
+# -Wgnu-null-pointer-arithmetics either. Since uJIT is built with -Wextra
+# (including -Wnull-pointer-arithmetics) and -Werror flags being set in
+# CMAKE_C_FLAGS list, compilation of src/utils/lj_alloc.c fails due to NULL
+# pointer arithmetics in TOP_FOOT_SIZE constant definition. Furthermore,
+# -Wno-gnu flag to silence GNU extension diagnostics for pointer arithmetic is
+# allowed since Clang 15 (https://github.com/llvm/llvm-project/issues/54444)
+# too. Considering everything above, tweak the CMAKE_C_FLAGS list for Clang
+# toolchain only for Clang 15.0.0 and later.
+# XXX: Unlike Linux distributions, we only support one version of macOS, so the
+# compiler to be used is well-defined.
+# Taking into account all of the above, just provide a tiny tweak for
+# CMAKE_C_FLAGS, nothing more.
+set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wno-gnu-null-pointer-arithmetic")
