Add semantic version checks for CCCL package.

share/cmake/cccl/cccl-config-version.cmake

@@ -1,13 +1,23 @@
-# TODO we should parse this from a header, and update to CalVer if that's still POR
+# TODO How should we encode this as a source of truth?
 set(CCCL_VERSION_MAJOR 2)
 set(CCCL_VERSION_MINOR 1)
 set(CCCL_VERSION_PATCH 0)
 set(CCCL_VERSION_TWEAK 0)
 
 set(CCCL_VERSION "${CCCL_VERSION_MAJOR}.${CCCL_VERSION_MINOR}.${CCCL_VERSION_PATCH}.${CCCL_VERSION_TWEAK}")
 
-# TODO decide and implement versioning logic.
 set(PACKAGE_VERSION ${CCCL_VERSION})
-set(PACKAGE_VERSION_COMPATIBLE TRUE)
-set(PACKAGE_VERSION_EXACT TRUE)
+set(PACKAGE_VERSION_COMPATIBLE FALSE)
+set(PACKAGE_VERSION_EXACT FALSE)
 set(PACKAGE_VERSION_UNSUITABLE FALSE)
+gi
+# Semantic versioning:
+if(PACKAGE_VERSION VERSION_GREATER_EQUAL PACKAGE_FIND_VERSION)
+  if(CCCL_VERSION_MAJOR VERSION_EQUAL PACKAGE_FIND_VERSION_MAJOR)
+    set(PACKAGE_VERSION_COMPATIBLE TRUE)
+  endif()
+
+  if(PACKAGE_FIND_VERSION VERSION_EQUAL PACKAGE_VERSION)
+    set(PACKAGE_VERSION_EXACT TRUE)
+  endif()
+endif()