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Author: kinke

.github/actions/3-build-native/action.yml

@@ -22,8 +22,9 @@ runs:
         build_dir: build
         host_dc: ../bootstrap-ldc/bin/ldmd2
         specify_install_dir: true
-        # FIXME: sporadic compiler crashes on macOS arm64 when using mimalloc *and* mixing LLVM versions for Xcode clang/host LDC:
-        # libc++abi: Pure virtual function called!
+        # FIXME: mimalloc on macOS is tricky - when mixing newer LLVM from bootstrap LDC with older LLVM from Xcode clang,
+        #        causing *sporadic* compiler crashes: `libc++abi: Pure virtual function called!`
+        #        on x86_64, this is 'fixed' by using LTO - on arm64, this doesn't suffice
         cmake_flags: >-
           ${{ (runner.os != 'Windows' && !(runner.os == 'macOS' && inputs.arch == 'arm64')) && '-DALTERNATIVE_MALLOC_O="$PWD/../build-mimalloc/CMakeFiles/mimalloc-obj.dir/src/static.c.o"' || '' }}
           ${{ inputs.cmake_flags }}

.github/workflows/main.yml

@@ -86,6 +86,8 @@ jobs:
             arch: arm64
             extra_cmake_flags: >-
               -DD_COMPILER_FLAGS="-O -flto=full -defaultlib=phobos2-ldc-lto,druntime-ldc-lto -L-exported_symbol '-L__*' -L-w"
+            # FIXME: cannot enable LTO for C++ parts too, due to: `LLVM ERROR: Unsupported stack probing method` when linking ldc2
+            #        (apparently from bitcode files compiled with older Xcode clang)
             #  -DEXTRA_CXXFLAGS=-flto=full
             with_pgo: true