Drop feature_args call in favor of letting pkgconfig do this directly

mesonbuild/interpreter.py

@@ -655,7 +655,6 @@ class CompilerHolder(InterpreterObject):
                              'get_supported_arguments': self.get_supported_arguments_method,
                              'first_supported_argument': self.first_supported_argument_method,
                              'unittest_args': self.unittest_args_method,
-                             'feature_args': self.feature_args_method,
                              'symbols_have_underscore_prefix': self.symbols_have_underscore_prefix_method,
                              })
 
@@ -752,12 +751,6 @@ class CompilerHolder(InterpreterObject):
         '''
         return self.compiler.symbols_have_underscore_prefix(self.environment)
 
-    def feature_args_method(self, args, kwargs):
-        # At time, only D compilers have this feature.
-        if not hasattr(self.compiler, 'get_feature_args'):
-            raise InterpreterException('This {} compiler has no feature arguments.'.format(self.compiler.get_display_language()))
-        return self.compiler.get_feature_args(kwargs)
-
     def unittest_args_method(self, args, kwargs):
         '''
         This function is deprecated and should not be used.

mesonbuild/modules/pkgconfig.py

@@ -121,7 +121,7 @@ class PkgConfigModule(ExtensionModule):
 
     @permittedKwargs({'libraries', 'version', 'name', 'description', 'filebase',
                       'subdirs', 'requires', 'requires_private', 'libraries_private',
-                      'install_dir', 'extra_cflags', 'variables', 'url'})
+                      'install_dir', 'extra_cflags', 'variables', 'url', 'd_feature_versions'})
     def generate(self, state, args, kwargs):
         if len(args) > 0:
             raise mesonlib.MesonException('Pkgconfig_gen takes no positional arguments.')
@@ -148,6 +148,12 @@ class PkgConfigModule(ExtensionModule):
         conflicts = mesonlib.stringlistify(kwargs.get('conflicts', []))
         extra_cflags = mesonlib.stringlistify(kwargs.get('extra_cflags', []))
 
+        dversions = kwargs.get('d_feature_versions', None)
+        if dversions:
+            compiler = state.environment.coredata.compilers.get('d')
+            if compiler:
+                extra_cflags.extend(compiler.get_feature_args({'versions': dversions}))
+
         def parse_variable_list(stringlist):
             reserved = ['prefix', 'libdir', 'includedir']
             variables = []