[PATCH v2 1/4] am: fail if no author line is given in --rebasing mode

[PATCH v2 1/4] am: fail if no author line is given in --rebasing mode

[Stephan Beyer]

This prevents a potential segmentation fault.

Signed-off-by: Stephan Beyer <s-beyer@gmx.net>
---
 builtin/am.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/builtin/am.c b/builtin/am.c
index 1aea657a7f..71da34913c 100644
--- a/builtin/am.c
+++ b/builtin/am.c
@@ -1272,7 +1272,8 @@ static void get_commit_info(struct am_state *state, struct commit *commit)
 	buffer = logmsg_reencode(commit, NULL, get_commit_output_encoding());

 	ident_line = find_commit_header(buffer, "author", &ident_len);
-
+	if (!ident_line)
+		die(_("no author line"));
 	if (split_ident_line(&id, ident_line, ident_len) < 0)
 		die(_("invalid ident line: %.*s"), (int)ident_len, ident_line);

--
2.23.0.43.g31ebfd7ae6.dirty

[PATCH v2 2/4] test-read-cache: fix maybe-uninitialized warning for namelen

[Stephan Beyer]

This is done by removing namelen at all. It is only used once
and simply strlen(name), hence we use strlen(name) directly.

Suggested-by: Jeff King <peff@peff.net>
Signed-off-by: Stephan Beyer <s-beyer@gmx.net>
---
 t/helper/test-read-cache.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/t/helper/test-read-cache.c b/t/helper/test-read-cache.c
index 7e79b555de..244977a29b 100644
--- a/t/helper/test-read-cache.c
+++ b/t/helper/test-read-cache.c
@@ -4,11 +4,10 @@

 int cmd__read_cache(int argc, const char **argv)
 {
-	int i, cnt = 1, namelen;
+	int i, cnt = 1;
 	const char *name = NULL;

 	if (argc > 1 && skip_prefix(argv[1], "--print-and-refresh=", &name)) {
-		namelen = strlen(name);
 		argc--;
 		argv++;
 	}
@@ -24,7 +23,7 @@ int cmd__read_cache(int argc, const char **argv)

 			refresh_index(&the_index, REFRESH_QUIET,
 				      NULL, NULL, NULL);
-			pos = index_name_pos(&the_index, name, namelen);
+			pos = index_name_pos(&the_index, name, strlen(name));
 			if (pos < 0)
 				die("%s not in index", name);
 			printf("%s is%s up to date\n", name,
--
2.23.0.43.g31ebfd7ae6.dirty

[PATCH v2 3/4] pack-objects: fix maybe-uninitialized warning for index_pos

[Stephan Beyer]

gcc 9.2.1 with -flto shows a maybe-uninitialized warning for index_pos
in builtin/pack-objects.c's add_object_entry().  Tracking it down,
the variable should be initialized in pack_objects.c's packlist_find().

The return value of locate_object_entry_hash(), which becomes index_pos,
is either (in case of found = 1) the position where the (already included)
OID is, or (in case of found = 0), index_pos is the position where the
(not yet included) OID will be after insertion (which takes place in
packlist_alloc() if the hash table is still large enough).

However, packlist_find() does not invoke locate_object_entry_hash() if
the index size is zero (which might be the case on the first run).
This is the only case where index_pos is undefined; and it is irrelevant
since the first run will increase the size of the hash table to 1024 and
then the undefined value index_pos is ignored.

This patch sets index_pos to zero on the first run to silence the warning.

Signed-off-by: Stephan Beyer <s-beyer@gmx.net>
---
 pack-objects.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/pack-objects.c b/pack-objects.c
index 52560293b6..726147a75d 100644
--- a/pack-objects.c
+++ b/pack-objects.c
@@ -74,8 +74,11 @@ struct object_entry *packlist_find(struct packing_data *pdata,
 	uint32_t i;
 	int found;

-	if (!pdata->index_size)
+	if (!pdata->index_size) {
+		if (index_pos)
+			*index_pos = 0; /* silence uninitialized warning */
 		return NULL;
+	}

 	i = locate_object_entry_hash(pdata, oid, &found);

--
2.23.0.43.g31ebfd7ae6.dirty

[PATCH v2 4/4] Silence false-positive maybe-uninitialized warnings found by gcc 9 -flto

[Stephan Beyer]

gcc 9.2.1 with -flto flag suspects some uninitialized variables which become
initialized in every code path where they are used.  These false positives
are "fixed" by this patch in the most naïve way.

This allows to compile git with gcc 9, link-time optimization, and using the
DEVELOPER=1 switch (which sets -Werror).

Signed-off-by: Stephan Beyer <s-beyer@gmx.net>
---
 bulk-checkin.c | 2 ++
 fast-import.c  | 3 ++-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/bulk-checkin.c b/bulk-checkin.c
index 39ee7d6107..87fa28c227 100644
--- a/bulk-checkin.c
+++ b/bulk-checkin.c
@@ -200,6 +200,8 @@ static int deflate_to_pack(struct bulk_checkin_state *state,
 	struct hashfile_checkpoint checkpoint;
 	struct pack_idx_entry *idx = NULL;

+	checkpoint.offset = 0;
+
 	seekback = lseek(fd, 0, SEEK_CUR);
 	if (seekback == (off_t) -1)
 		return error("cannot find the current offset");
diff --git a/fast-import.c b/fast-import.c
index b44d6a467e..58f73f9105 100644
--- a/fast-import.c
+++ b/fast-import.c
@@ -903,7 +903,8 @@ static int store_object(
 	struct object_entry *e;
 	unsigned char hdr[96];
 	struct object_id oid;
-	unsigned long hdrlen, deltalen;
+	unsigned long hdrlen;
+	unsigned long deltalen = 0;
 	git_hash_ctx c;
 	git_zstream s;

--
2.23.0.43.g31ebfd7ae6.dirty

Re: [PATCH v2 1/4] am: fail if no author line is given in --rebasing mode

[Stephan Beyer]

Hi,

just to make it also clear in this thread: you can ignore this patch
series in favor of the better patch series by Peff [1] that has found
its way to the mailing list at the same time.

1.
https://public-inbox.org/git/20190905224859.GA28660@sigill.intra.peff.net/

Stephan