Say when --track is useful in the git-checkout docs.

diff --git a/diffcore-rename.c b/diffcore-rename.c
index 6bde4396f212833cc1d411e723d5215c086e7c2d..41b35c3a9e6935f6cd8563de732321e74e115765 100644 (file)
--- a/diffcore-rename.c
+++ b/diffcore-rename.c
@@ -298,10 +298,25 @@ void diffcore_rename(struct diff_options *options)
                else if (detect_rename == DIFF_DETECT_COPY)
                        register_rename_src(p->one, 1, p->score);
        }
-       if (rename_dst_nr == 0 || rename_src_nr == 0 ||
-           (0 < rename_limit && rename_limit < rename_dst_nr))
+       if (rename_dst_nr == 0 || rename_src_nr == 0)
                goto cleanup; /* nothing to do */
 
+       /*
+        * This basically does a test for the rename matrix not
+        * growing larger than a "rename_limit" square matrix, ie:
+        *
+        *    rename_dst_nr * rename_src_nr > rename_limit * rename_limit
+        *
+        * but handles the potential overflow case specially (and we
+        * assume at least 32-bit integers)
+        */
+       if (rename_limit <= 0 || rename_limit > 32767)
+               rename_limit = 32767;
+       if (rename_dst_nr > rename_limit && rename_src_nr > rename_limit)
+               goto cleanup;
+       if (rename_dst_nr * rename_src_nr > rename_limit * rename_limit)
+               goto cleanup;
+
        /* We really want to cull the candidates list early
         * with cheap tests in order to avoid doing deltas.
         * The first round matches up the up-to-date entries,