nagfor OpenMP recognition.

mesonbuild/dependencies/misc.py

@@ -78,6 +78,12 @@ class OpenMPDependency(SystemDependency):
         language = kwargs.get('language')
         super().__init__('openmp', environment, kwargs, language=language)
         self.is_found = False
+        if self.clib_compiler.get_id() == 'nagfor':
+            # No macro defined for OpenMP, but OpenMP 3.1 is supported.
+            self.version = '3.1'
+            self.is_found = True
+            self.compile_args = self.link_args = self.clib_compiler.openmp_flags()
+            return
         if self.clib_compiler.get_id() == 'pgi':
             # through at least PGI 19.4, there is no macro defined for OpenMP, but OpenMP 3.1 is supported.
             self.version = '3.1'