Re: [PATCH] blame.c: replace instance of !oidcmp for oideq

René Scharfe [off-list ref] writes:

quoted

diff -u -p a/packfile.c b/packfile.c

--- a/packfile.c
+++ b/packfile.c

@@ -735,7 +735,7 @@ struct packed_git *add_packed_git(const
 	p->mtime = st.st_mtime;
 	if (path_len < the_hash_algo->hexsz ||
 	    get_sha1_hex(path + path_len - the_hash_algo->hexsz, p->hash))
-		hashclr(p->hash);
+		oidclr(p);
 	return p;
 }

Maybe it's worth being looser in our cocci patch definitions. I'm having
trouble thinking of a downside...

For transformations that change the type as in the example above we
should insist on getting the right one, otherwise we might introduce
bugs -- like in the example above.  p points to a struct packed_git and
not to a struct object_id, so this introduces a type mismatch.

;-)  A good counter-example.

We better make sure our semantic patches are safe, otherwise we have to
check all conversions very carefully, and then we might be better off
doing them manually..

Yes, that is a sensible suggestion.