Preserve coords on atomic TypeDecl

fixes #475

Author: eliben

pycparser/ast_transforms.py

@@ -168,6 +168,10 @@ def _fix_atomic_specifiers_once(
 
     assert isinstance(parent, c_ast.TypeDecl)
     assert grandparent is not None
+    if node.type.coord is None:
+        # Preserve the declarator coord for _Atomic(T) so TypeDecl doesn't lose
+        # its location when we replace the wrapper Typename.
+        node.type.coord = parent.coord
     cast(Any, grandparent).type = node.type
     if "_Atomic" not in node.type.quals:
         node.type.quals.append("_Atomic")

tests/test_c_parser.py

@@ -249,6 +249,13 @@ def test_coords(self):
         }"""
         self.assert_coord(self.parse(t6).ext[0].decl.type.args.params[1], 3, 17)
 
+        # Coord for _Atomic type decls
+        t7 = """
+        typedef _Atomic(char) atomic_char;
+        """
+        self.assert_coord(self.parse(t7).ext[0], 2, 31)
+        self.assert_coord(self.parse(t7).ext[0].type, 2, 31)
+
     def test_forloop_coord(self):
         t = """\
         void foo() {