CHANGELOG.md

+# [1.0.0-alpha.15](https://git.gitlab.arm.com/bazel/rules_toolchain/compare/v1.0.0-alpha.14...v1.0.0-alpha.15) (2024-01-10)
+
+### Bug Fixes
+
+- **sw_vers:** support single and double Darwin OS versions ([bb887b9](https://git.gitlab.arm.com/bazel/rules_toolchain/commit/bb887b98b601be790b3a1cc95486de9ed30f9a83))
+
 # [1.0.0-alpha.14](https://git.gitlab.arm.com/bazel/rules_toolchain/compare/v1.0.0-alpha.13...v1.0.0-alpha.14) (2024-01-09)
 
 ### Bug Fixes

MODULE.bazel

 module(
     name = "rules_toolchain",
-    version = "1.0.0-alpha.14",
+    version = "1.0.0-alpha.15",
     bazel_compatibility = [
         ">=7.0.0",
     ],

toolchain/local/triplet/os.bzl

@@ -76,6 +76,8 @@ def _sw_vers(rctx, path):
     version = result.stdout.strip()
 
     major, minor, patch = split(version, ".", {
+        1: lambda x: (x, 0, 0),
+        2: lambda x, y: (x, y, 0),
         3: lambda x, y, z: (x, y, z),
     })