[[[
Just add some debugging prints.

* subversion/libsvn_repos/fs-wrap.c
  (svn_repos_fs_get_mergeinfo): Add debugging prints that indicate
    whether and how the mergeinfo authz check is happening.

* subversion/svnserve/serve.c
  (must_have_access): Add a debugging print that shows this function
    was called on a given path.
]]]

Index: subversion/libsvn_repos/fs-wrap.c
===================================================================
--- subversion/libsvn_repos/fs-wrap.c	(revision 29051)
+++ subversion/libsvn_repos/fs-wrap.c	(working copy)
@@ -613,6 +613,25 @@
            apr_hash_index_t *hi;
            apr_hash_t *original_paths_hash, *readable_paths_hash;
 
+#define KFF_DEBUG 1
+
+           if (KFF_DEBUG)
+             {
+               FILE *fp = fopen("/tmp/kff.out", "a");
+               if (fp == NULL)
+                 exit(1);
+               fprintf(fp, "KFF: include_descendants is true\n");
+               fprintf(fp, "KFF: paths: '%s'\n",
+                       svn_cstring_join((apr_array_header_t *) paths,
+                                        ", ", pool));
+               fprintf(fp, "KFF: readable_paths: '%s'\n",
+                       svn_cstring_join((apr_array_header_t *) readable_paths,
+                                        ", ", pool));
+               fprintf(fp, "KFF: *mergeinfo count: %d\n",
+                       apr_hash_count(*mergeinfo));
+               fclose(fp);
+             }
+
            /* Make lookups easy by converting to hash. */
            SVN_ERR(svn_hash_from_cstring_keys(&original_paths_hash,
                                               paths, pool));
@@ -639,9 +658,34 @@
                path = key;
                raw_mergeinfo_string = val;
 
+               if (KFF_DEBUG)
+                 {
+                   FILE *fp = fopen("/tmp/kff.out", "a");
+                   if (fp == NULL)
+                     exit(1);
+                   fprintf(fp, "KFF: loop hit '%s'\n", path);
+                   fprintf(fp, "KFF: mergeinfo for '%s':\n", path);
+                   fprintf(fp, "'%s'\n",
+                           (char *) apr_hash_get(*mergeinfo, path,
+                                                 APR_HASH_KEY_STRING));
+                   fprintf(fp, "KFF: (rp_h == op_h? --> %d)\n",
+                           readable_paths_hash == original_paths_hash);
+                   fclose(fp);
+                 }
+
                if (! apr_hash_get(readable_paths_hash, path,
                                   APR_HASH_KEY_STRING))
                  {
+                   if (KFF_DEBUG)
+                     {
+                       FILE *fp = fopen("/tmp/kff.out", "a");
+                       if (fp == NULL)
+                         exit(1);
+                       fprintf(fp, "KFF: '%s' is not in readable_paths\n",
+                               path);
+                       fclose(fp);
+                     }
+
                    /* It's not in readable_paths, so if it *is* in
                       the original paths, that means it was already
                       authz-checked and found unreadable -- in which
@@ -650,6 +694,16 @@
                        && apr_hash_get(original_paths_hash, path,
                                        APR_HASH_KEY_STRING))
                      {
+                       if (KFF_DEBUG)
+                         {
+                           FILE *fp = fopen("/tmp/kff.out", "a");
+                           if (fp == NULL)
+                             exit(1);
+                           fprintf(fp, "KFF: '%s' is easily unreadable\n",
+                                   path);
+                           fclose(fp);
+                         }
+
                        apr_hash_set(*mergeinfo, path, APR_HASH_KEY_STRING,
                                     NULL);
                      }
@@ -661,6 +715,16 @@
                        svn_boolean_t readable;
                        SVN_ERR(authz_read_func(&readable, root, path,
                                                authz_read_baton, iterpool));
+                       if (KFF_DEBUG)
+                         {
+                           FILE *fp = fopen("/tmp/kff.out", "a");
+                           if (fp == NULL)
+                             exit(1);
+                           fprintf(fp, "KFF: '%s' authz-checked --> %d\n",
+                                   path, readable);
+                           fclose(fp);
+                         }
+
                        if (! readable)
                          apr_hash_set(*mergeinfo, path, APR_HASH_KEY_STRING,
                                       NULL);
Index: subversion/svnserve/serve.c
===================================================================
--- subversion/svnserve/serve.c	(revision 29051)
+++ subversion/svnserve/serve.c	(working copy)
@@ -499,6 +499,14 @@
       ))
     SVN_ERR(auth_request(conn, pool, b, req, TRUE));
 
+  if (1) /* kff */
+    {
+      FILE *fp = fopen("/tmp/kff.out", "a");
+      if (fp == NULL)
+        exit(1);
+      fprintf(fp, "KFF: must_have_access('%s')\n", path);
+      fclose(fp);
+    }
   /* Now that an authentication has been done get the new take of
      authz on the request. */
   if (! lookup_access(pool, b, required, path, needs_username))