compilers: Add Apple subclasses for ObjC and ObjC++

These are needed because in some cases we need to be able to know if
we're using vanilla clang or Apple's clang.

mesonbuild/compilers/__init__.py

@@ -36,6 +36,8 @@ __all__ = [
 
     'AppleClangCCompiler',
     'AppleClangCPPCompiler',
+    'AppleClangObjCCompiler',
+    'AppleClangObjCPPCompiler',
     'ArmCCompiler',
     'ArmCPPCompiler',
     'ArmclangCCompiler',
@@ -183,11 +185,13 @@ from .fortran import (
 from .java import JavaCompiler
 from .objc import (
     ObjCCompiler,
+    AppleClangObjCCompiler,
     ClangObjCCompiler,
     GnuObjCCompiler,
 )
 from .objcpp import (
     ObjCPPCompiler,
+    AppleClangObjCPPCompiler,
     ClangObjCPPCompiler,
     GnuObjCPPCompiler,
 )

mesonbuild/compilers/objc.py

@@ -92,3 +92,8 @@ class ClangObjCCompiler(ClangCompiler, ObjCCompiler):
                           '1': default_warn_args,
                           '2': default_warn_args + ['-Wextra'],
                           '3': default_warn_args + ['-Wextra', '-Wpedantic']}
+
+
+class AppleClangObjCCompiler(ClangObjCCompiler):
+
+    """Handle the differences between Apple's clang and vanilla clang."""

mesonbuild/compilers/objcpp.py

@@ -90,3 +90,9 @@ class ClangObjCPPCompiler(ClangCompiler, ObjCPPCompiler):
                           '1': default_warn_args,
                           '2': default_warn_args + ['-Wextra'],
                           '3': default_warn_args + ['-Wextra', '-Wpedantic']}
+
+
+
+class AppleClangObjCPPCompiler(ClangObjCPPCompiler):
+
+    """Handle the differences between Apple's clang and vanilla clang."""

mesonbuild/environment.py

@@ -74,6 +74,8 @@ from .compilers import (
     ArmclangCPPCompiler,
     AppleClangCCompiler,
     AppleClangCPPCompiler,
+    AppleClangObjCCompiler,
+    AppleClangObjCPPCompiler,
     ClangCCompiler,
     ClangCPPCompiler,
     ClangObjCCompiler,
@@ -1506,7 +1508,7 @@ class Environment:
     def detect_objcpp_compiler(self, for_machine: MachineInfo) -> 'Compiler':
         return self._detect_objc_or_objcpp_compiler(for_machine, False)
 
-    def _detect_objc_or_objcpp_compiler(self, for_machine: MachineInfo, objc: bool) -> 'Compiler':
+    def _detect_objc_or_objcpp_compiler(self, for_machine: MachineChoice, objc: bool) -> 'Compiler':
         popen_exceptions = {}
         compilers, ccache, exe_wrap = self._get_compilers('objc' if objc else 'objcpp', for_machine)
         is_cross = self.is_cross_build(for_machine)
@@ -1535,6 +1537,9 @@ class Environment:
                     exe_wrap, defines, linker=linker)
             if 'clang' in out:
                 linker = None
+                if 'Apple' in out:
+                    comp = AppleClangObjCCompiler if objc else AppleClangObjCPPCompiler
+                else:
                     comp = ClangObjCCompiler if objc else ClangObjCPPCompiler
                 if 'windows' in out or self.machines[for_machine].is_windows():
                     # If we're in a MINGW context this actually will use a gnu style ld