diff --git a/mypy/build.py b/mypy/build.py
index f8a9294ebd766..525d5f436e7e1 100644
--- a/mypy/build.py
+++ b/mypy/build.py
@@ -2207,7 +2207,6 @@ def parse_inline_configuration(self, source: str) -> None:
         """Check for inline mypy: options directive and parse them."""
         flags = get_mypy_comments(source)
         if flags:
-            # TODO: should this be captured as well for parser errors?
             changes, config_errors = parse_mypy_comments(flags, self.options)
             self.options = self.options.apply_changes(changes)
             self.manager.errors.set_file(self.xpath, self.id, self.options)
diff --git a/mypy/config_parser.py b/mypy/config_parser.py
index f6c889c9de96b..371c9bd898d7b 100644
--- a/mypy/config_parser.py
+++ b/mypy/config_parser.py
@@ -454,7 +454,7 @@ def parse_section(
                     else:
                         msg = f"{prefix}Unrecognized report type: {key}"
                         raise argparse.ArgumentTypeError(msg)
-                if key.startswith("x_"):
+                elif key.startswith("x_"):
                     pass  # Don't complain about `x_blah` flags
                 elif key.startswith("no_") and hasattr(template, key[3:]):
                     options_key = key[3:]
@@ -489,7 +489,6 @@ def parse_section(
                     v = not v
             elif callable(ct):
                 if invert:
-                    # TODO: should this be captured or it is okay to ignore
                     print(f"{prefix}Can not invert non-boolean key {options_key}", file=stderr)
                     continue
                 try:
@@ -499,7 +498,6 @@ def parse_section(
                     raise argparse.ArgumentTypeError(msg) from err
             else:
                 print(f"{prefix}Don't know what type {key} should have", file=stderr)
-                # TODO: should this be captured or it is okay to ignore as type is not known
                 continue
         except ValueError as err:
             msg = f"{prefix}{key}: {err}"
diff --git a/mypy/main.py b/mypy/main.py
index 329bfe51c061f..2de206074c6b9 100644
--- a/mypy/main.py
+++ b/mypy/main.py
@@ -1252,8 +1252,7 @@ def set_strict_flags() -> None:
     try:
         parse_config_file(options, set_strict_flags, config_file, stdout, stderr)
     except (argparse.ArgumentTypeError, ValueError) as err:
-        stderr.write(f"{err}")
-        sys.exit(1)
+        raise SystemExit(str(err)) from err
 
     # Set strict flags before parsing (if strict mode enabled), so other command
     # line options can override.