diff --git a/CMakeLists.txt b/CMakeLists.txt
index b1c567d..0e74411 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -17,6 +17,8 @@ set (project_version "0.9.7")
 
 # Try to append commit ID if it follows a version tag.  It might be nicer if
 # we could also detect dirty worktrees but that's very hard to get right.
+# If we didn't need this for CPack, we could use add_custom_command to generate
+# a version source/include file.
 find_package (Git)
 set (git_head "${PROJECT_SOURCE_DIR}/.git/HEAD")
 if (GIT_FOUND AND EXISTS "${git_head}")