Wire up locations in a couple more warnings

These are the remaining warnings in the parser, where we have the location
to hand.

mesonbuild/interpreter.py

@@ -1574,7 +1574,7 @@ class Interpreter(InterpreterBase):
         modname = args[0]
         if modname.startswith('unstable-'):
             plainname = modname.split('-', 1)[1]
-            mlog.warning('Module %s has no backwards or forwards compatibility and might not exist in future releases.' % modname)
+            mlog.warning('Module %s has no backwards or forwards compatibility and might not exist in future releases' % modname, location=node)
             modname = 'unstable_' + plainname
         if modname not in self.environment.coredata.modules:
             try:
@@ -2732,7 +2732,7 @@ root and issuing %s.
                     mlog.warning(
                         "The variable(s) %s in the input file %s are not "
                         "present in the given configuration data" % (
-                            var_list, inputfile))
+                            var_list, inputfile), location=node)
             else:
                 mesonlib.dump_conf_header(ofile_abs, conf.held_object)
             conf.mark_used()

run_unittests.py

@@ -1710,10 +1710,15 @@ int main(int argc, char **argv) {
     def test_warning_location(self):
         tdir = os.path.join(self.unit_test_dir, '20 warning location')
         out = self.init(tdir)
-        self.assertRegex(out, r'WARNING: Keyword argument "link_with" defined multiple times in file meson.build, line 4')
-        self.assertRegex(out, r'WARNING: Keyword argument "link_with" defined multiple times in file sub' + re.escape(os.path.sep) + r'meson.build, line 3')
-        self.assertRegex(out, r'WARNING: a warning of some sort in file meson.build, line 6')
-        self.assertRegex(out, r'WARNING: subdir warning in file sub' + re.escape(os.path.sep) + r'meson.build, line 4')
+        for expected in [
+            r'WARNING: Keyword argument "link_with" defined multiple times in file meson.build, line 4',
+            r'WARNING: Keyword argument "link_with" defined multiple times in file sub' + os.path.sep + r'meson.build, line 3',
+            r'WARNING: a warning of some sort in file meson.build, line 6',
+            r'WARNING: subdir warning in file sub' + os.path.sep + r'meson.build, line 4',
+            r'WARNING: Module unstable-simd has no backwards or forwards compatibility and might not exist in future releases in file meson.build, line 7',
+            r"WARNING: The variable(s) 'MISSING' in the input file conf.in are not present in the given configuration data in file meson.build, line 10",
+        ]:
+            self.assertRegex(out, re.escape(expected))
 
     def test_templates(self):
         ninja = detect_ninja()

test cases/unit/20 warning location/conf.in

@@ -0,0 +1 @@
+@MISSING@

test cases/unit/20 warning location/meson.build

@@ -1,6 +1,10 @@
-project('duplicate kwarg', 'c')
+project('warning location', 'c')
 a = library('liba', 'a.c')
 b = library('libb', 'b.c')
 executable('main', 'main.c', link_with: a, link_with: b)
 subdir('sub')
 warning('a warning of some sort')
+import('unstable-simd')
+
+conf_data = configuration_data()
+configure_file(input: 'conf.in' , output: 'conf', configuration: conf_data)