Add forgotten Lit features

Author: ldionne

libcxx/utils/libcxx/test/features.py

@@ -724,17 +724,24 @@ def check_gdb(cfg):
 # Helpers to define correspondances between LLVM versions and vendor system versions.
 # Those are used for backdeployment features below, do not use directly in tests.
 DEFAULT_FEATURES += [
+    Feature(
+        name="_target-has-llvm-19",
+        when=lambda cfg: BooleanExpression.evaluate(
+            "_target-has-llvm-20 || target={{.+}}-apple-macosx{{15.[4-9](.\d+)?}}",
+            cfg.available_features,
+        ),
+    ),
     Feature(
         name="_target-has-llvm-18",
         when=lambda cfg: BooleanExpression.evaluate(
-            "target={{.+}}-apple-macosx{{15(.[0-9]+)?(.[0-9]+)?}}",
+            "_target-has-llvm-19 || target={{.+}}-apple-macosx{{15.[0-3](.\d+)?}}",
             cfg.available_features,
         ),
     ),
     Feature(
         name="_target-has-llvm-17",
         when=lambda cfg: BooleanExpression.evaluate(
-            "_target-has-llvm-18 || target={{.+}}-apple-macosx{{14.[4-9](.[0-9]+)?}} || target={{.+}}-apple-macosx{{1[5-9]([.].+)?}}",
+            "_target-has-llvm-18 || target={{.+}}-apple-macosx{{14.[4-9](.\d+)?}}",
             cfg.available_features,
         ),
     ),