Skip the git-rev in the hash for now (from a5e8d632)

It may be potentially expensive to fork-exec a git call to get the HEAD
revision, and it's not clear whether it's even needed.  We can always
throw this back on if we find a meaningful usage scenario.

1 files changed, 4 insertions, 1 deletions

diff --git a/hash.cxx b/hash.cxx
index 649e7ec0..3ff6848d 100644
--- a/hash.cxx
+++ b/hash.cxx
@@ -97,7 +97,10 @@ get_base_hash (systemtap_session& s, hash& h)
 
   // If the kernel is a git working directory, then add the git HEAD
   // revision to our hash as well.
-  h.add(git_revision(s.kernel_build_tree));
+  // XXX avoiding this for now, because it's potentially expensive and has
+  // uncertain gain.  The only corner case that this may help is if a developer
+  // is switching the source tree without rebuilding the kernel...
+  ///h.add(git_revision(s.kernel_build_tree));
 
   // Hash runtime path (that gets added in as "-R path").
   h.add(s.runtime_path);