backends/ninja: run ranlib -c $out when using the apple ar

Apple's AR is old, and doesn't add externed symbols to the symbol table,
instead relying on the user calling ranlib with -c. We need to do that
for the user

mesonbuild/backend/ninjabackend.py

@@ -42,7 +42,7 @@
     PGICCompiler,
     VisualStudioLikeCompiler,
 )
-from ..linkers import ArLinker, RSPFileSyntax
+from ..linkers import ArLinker, AppleArLinker, RSPFileSyntax
 from ..mesonlib import (
     File, LibType, MachineChoice, MesonException, OrderedSet, PerMachine,
     ProgressBar, quote_arg
@@ -2028,7 +2028,7 @@ def generate_static_link_rules(self):
             if static_linker is None:
                 continue
             rule = 'STATIC_LINKER{}'.format(self.get_rule_suffix(for_machine))
-            cmdlist = []
+            cmdlist: T.List[T.Union[str, NinjaCommandArg]] = []
             args = ['$in']
             # FIXME: Must normalize file names with pathlib.Path before writing
             #        them out to fix this properly on Windows. See:
@@ -2042,6 +2042,17 @@ def generate_static_link_rules(self):
             cmdlist += static_linker.get_exelist()
             cmdlist += ['$LINK_ARGS']
             cmdlist += NinjaCommandArg.list(static_linker.get_output_args('$out'), Quoting.none)
+            # The default ar on MacOS (at least through version 12), does not
+            # add extern'd variables to the symbol table by default, and
+            # requires that apple's ranlib be called with a special flag
+            # instead after linking
+            if isinstance(static_linker, AppleArLinker):
+                # This is a bit of a hack, but we assume that that we won't need
+                # an rspfile on MacOS, otherwise the arguments are passed to
+                # ranlib, not to ar
+                cmdlist.extend(args)
+                args = []
+                cmdlist.extend(['&&', 'ranlib', '-c', '$out'])
             description = 'Linking static target $out'
             if num_pools > 0:
                 pool = 'pool = link_pool'