Merge branch 'maint'

* maint:
  Break down no-lstat() condition checks in verify_uptodate()
  t7400: fix bogus test failure with symlinked trash
  Documentation: clarify the invalidated tree entry format

Documentation/technical/index-format.txt

@@ -147,8 +147,9 @@ GIT index format
   - 160-bit object name for the object that would result from writing
     this span of index as a tree.
 
-  An entry can be in an invalidated state and is represented by having -1
+  An entry can be in an invalidated state and is represented by having
-  in the entry_count field.
+  -1 in the entry_count field. In this case, there is no object name
+  and the next entry starts immediately after the newline.
 
   The entries are written out in the top-down, depth-first order.  The
   first entry represents the root level of the repository, followed by the

t/t7400-submodule-basic.sh

@@ -47,8 +47,10 @@ test_expect_success 'setup - repository to add submodules to' '
 '
 
 # The 'submodule add' tests need some repository to add as a submodule.
-# The trash directory is a good one as any.
+# The trash directory is a good one as any. We need to canonicalize
-submodurl=$TRASH_DIRECTORY
+# the name, though, as some tests compare it to the absolute path git
+# generates, which will expand symbolic links.
+submodurl=$(pwd -P)
 
 listbranches() {
 	git for-each-ref --format='%(refname)' 'refs/heads/*'

unpack-trees.c

@@ -1168,11 +1168,22 @@ static int verify_uptodate_1(struct cache_entry *ce,
 {
 	struct stat st;
 
-	if (o->index_only || (!((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce)) && (o->reset || ce_uptodate(ce))))
+	if (o->index_only)
+		return 0;
+
+	/*
+	 * CE_VALID and CE_SKIP_WORKTREE cheat, we better check again
+	 * if this entry is truly up-to-date because this file may be
+	 * overwritten.
+	 */
+	if ((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce))
+		; /* keep checking */
+	else if (o->reset || ce_uptodate(ce))
 		return 0;
 
 	if (!lstat(ce->name, &st)) {
-		unsigned changed = ie_match_stat(o->src_index, ce, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
+		int flags = CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE;
+		unsigned changed = ie_match_stat(o->src_index, ce, &st, flags);
 		if (!changed)
 			return 0;
 		/*