setup_git_env: avoid blind fall-back to ".git"

diff --git a/cache.h b/cache.h
index f7ee4145634762a42663df3c69b095d64d919d01..607fe6ed30f6003009217ec22de13873e57589b4 100644 (file)
--- a/cache.h
+++ b/cache.h
@@ -903,8 +903,8 @@ extern char *sha1_pack_index_name(const unsigned char *sha1);
  * The result will be at least `len` characters long, and will be NUL
  * terminated.
  *
- * The non-`_r` version returns a static buffer which will be overwritten by
- * subsequent calls.
+ * The non-`_r` version returns a static buffer which remains valid until 4
+ * more calls to find_unique_abbrev are made.
  *
  * The `_r` variant writes to a buffer supplied by the caller, which must be at
  * least `GIT_SHA1_HEXSZ + 1` bytes. The return value is the number of bytes