Support building on msys/clang64 (#276)

* Support building on msys/clang64
* Support libc++

.github/workflows/main.yml

@@ -193,7 +193,7 @@ jobs:
       matrix:
         # Build each combination of OS and release/debug variants
         os: [ windows-2019 ]
-        msystem: [ ucrt64, mingw64 ]
+        msystem: [ ucrt64, mingw64, clang64 ]
         build-type: [ Release, Debug ]
         include:
           - msystem: ucrt64
@@ -202,6 +202,10 @@ jobs:
           - msystem: mingw64
             package-prefix: x86_64
             cmake-flags: LDFLAGS="-fuse-ld=lld -lstdc++ -lgcc_s"
+          - msystem: clang64
+            package-prefix: clang-x86_64
+            cmake-flags: LDFLAGS="-lc++"
+            ctest-flags: -E UnexpectedException*
       # Don't abort runners if a single one fails
       fail-fast: false
     runs-on: ${{ matrix.os }}
@@ -220,7 +224,7 @@ jobs:
       run: |        
         mkdir build
         cd build
-        ${{ matrix.cmake-flags }} cmake .. -DTESTS=ON -DCMAKE_C_COMPILER="clang" -DCMAKE_CXX_COMPILER="clang" -DCMAKE_BUILD_TYPE=${{ matrix.build-type }}
+        ${{ matrix.cmake-flags }} cmake .. -DTESTS=ON -DCMAKE_C_COMPILER="clang" -DCMAKE_CXX_COMPILER="clang++" -DCMAKE_BUILD_TYPE=${{ matrix.build-type }}
     - name: Build
       working-directory: build
       run: |
@@ -228,8 +232,15 @@ jobs:
     - name: Test
       working-directory: build
       run: |
-        ctest -j 4 --output-on-failure -T test
-
+        ctest -j 4 --output-on-failure -T test ${{ matrix.ctest-flags }}
+    - name: Install
+      working-directory: build
+      run: |
+        cmake --install . --prefix=../dist
+    - uses: actions/upload-artifact@v4
+      with:
+        name: ${{ matrix.msystem }}-${{ matrix.build-type }}
+        path: dist/
 
   # Fake check that can be used as a branch-protection rule.
   all-checks:

CMakeLists.txt

@@ -20,6 +20,13 @@ endif()
 
 enable_language(OBJC OBJCXX)
 
+if (MINGW)
+	set(CMAKE_IMPORT_LIBRARY_SUFFIX ".dll.a")
+	set(CMAKE_LINK_LIBRARY_SUFFIX "")
+	set(CMAKE_SHARED_LIBRARY_PREFIX "lib")
+	set(CMAKE_OBJCXX_IMPLICIT_INCLUDE_DIRECTORIES ${CMAKE_CXX_IMPLICIT_INCLUDE_DIRECTORIES})
+endif ()
+
 INCLUDE (CheckCXXSourceCompiles)
 INCLUDE (FetchContent)
 
@@ -301,6 +308,9 @@ if (NOT CMAKE_INSTALL_LIBDIR)
 	set(CMAKE_INSTALL_LIBDIR lib)
 endif ()
 
+if (NOT CMAKE_INSTALL_BINDIR)
+	set(CMAKE_INSTALL_BINDIR bin)
+endif ()
 
 set(GNUSTEP_INSTALL_TYPE ${DEFAULT_INSTALL_TYPE} CACHE STRING
 	"GNUstep installation type.  Options are NONE, SYSTEM, NETWORK or LOCAL.")

objcxx_eh.cc

@@ -8,6 +8,12 @@ typedef struct objc_object* id;
 #include "objc/runtime.h"
 #include "objc/objc-arc.h"
 
+#ifndef DEBUG_EXCEPTIONS
+#define DEBUG_LOG(...)
+#else
+#define DEBUG_LOG(str, ...) fprintf(stderr, str, ## __VA_ARGS__)
+#endif
+
 /**
  * Helper function that has a custom personality function.
  * This calls `cxx_throw` and has a destructor that must be run.  We intercept
@@ -295,10 +301,18 @@ namespace gnustep
 		/* libc++-abi does not have  __is_pointer_p and won't do the double dereference 
 		 * required to get the object pointer. We need to do it ourselves if we have
 		 * caught an exception with libc++'s exception class. */
+#ifndef __MINGW32__
 		 if (cxx_exception_class == llvm_cxx_exception_class) {
 			 return **(id**)obj;
 		 }
 		 return *(id*)obj;
+#else
+#ifdef _LIBCPP_VERSION
+		return **(id**)obj;
+#else
+		return *(id*)obj;
+#endif // _LIBCPP_VERSION
+#endif // __MINGW32__
 	 }
 };
 
@@ -355,14 +369,17 @@ bool gnustep::libobjc::__objc_id_type_info::__do_catch(const type_info *thrownTy
 	// Id catch matches any ObjC throw
 	if (dynamic_cast<const __objc_class_type_info*>(thrownType))
 	{
-		*obj = *(id*)obj;
+		*obj = dereference_thrown_object_pointer(obj);
+		DEBUG_LOG("gnustep::libobjc::__objc_id_type_info::__do_catch caught 0x%x\n", *obj);
 		return true;
 	}
 	if (dynamic_cast<const __objc_id_type_info*>(thrownType))
 	{
-		*obj = *(id*)obj;
+		*obj = dereference_thrown_object_pointer(obj);
+		DEBUG_LOG("gnustep::libobjc::__objc_id_type_info::__do_catch caught 0x%x\n", *obj);
 		return true;
 	}
+	DEBUG_LOG("gnustep::libobjc::__objc_id_type_info::__do_catch returning false\n");
 	return false;
 };
 
@@ -494,6 +511,7 @@ extern "C" void test_cxx_eh_implementation()
 #else
 static void eh_cleanup(void *exception)
 {
+	DEBUG_LOG("eh_cleanup: Releasing 0x%x\n", *(id*)exception);
 	objc_release(*(id*)exception);
 }
 
@@ -504,6 +522,7 @@ void objc_exception_throw(id object)
 	id *exc = (id *)__cxa_allocate_exception(sizeof(id));
 	*exc = object;
 	objc_retain(object);
+	DEBUG_LOG("objc_exception_throw: Throwing 0x%x\n", *exc);
 	__cxa_throw(exc, & __objc_id_type_info, eh_cleanup);
 }
 #endif