Subject: Re: [PATCH v3 2/3] refs: add option core.logAllRefUpdates = always

From: Junio C Hamano <[email-masked]>
Date: Mon, 30 Jan 2017 14:57:15 -0800

Junio C Hamano <[email-masked]> writes:

>> diff --git a/builtin/checkout.c b/builtin/checkout.c
>> index bfe685c..81ea2ed 100644
>> --- a/builtin/checkout.c
>> +++ b/builtin/checkout.c
>> @@ -612,14 +612,12 @@ static void update_refs_for_switch(const struct checkout_opts *opts,
>>  	const char *old_desc, *reflog_msg;
>>  	if (opts->new_branch) {
>>  		if (opts->new_orphan_branch) {
>> -			if (opts->new_branch_log && !log_all_ref_updates) {
>> +			const char *refname = mkpathdup("refs/heads/%s", opts->new_orphan_branch);
>> ...
>>  				if (ret) {
>>  					fprintf(stderr, _("Can not do reflog for '%s': %s\n"),
>>  						opts->new_orphan_branch, err.buf);
>
> Here you need to have another free(), as this block makes an early
> return and you end up leaking refname.

I am building with the attached patch squashed on top.  

The extra free(refname) is to plug the leak I pointed out, and the
type of refname is no longer const, because "const char *" cannot be
free()d without casting, and in this codepath I do not see a reason
to mark it as const.

When queued on top of 4e59582ff7 ("Seventh batch for 2.12",
2017-01-23), however, this fails t2017#9 (orphan with -l makes
reflog when core.logAllRefUpdates = false).

diff --git a/builtin/checkout.c b/builtin/checkout.c
index 81ea2eda99..e1a60fd8ea 100644
--- a/builtin/checkout.c
+++ b/builtin/checkout.c
@@ -612,7 +612,9 @@ static void update_refs_for_switch(const struct checkout_opts *opts,
 	const char *old_desc, *reflog_msg;
 	if (opts->new_branch) {
 		if (opts->new_orphan_branch) {
-			const char *refname = mkpathdup("refs/heads/%s", opts->new_orphan_branch);
+			char *refname;
+
+			refname = mkpathdup("refs/heads/%s", opts->new_orphan_branch);
 			if (opts->new_branch_log && should_autocreate_reflog(refname)) {
 				int ret;
 				struct strbuf err = STRBUF_INIT;
@@ -622,6 +624,7 @@ static void update_refs_for_switch(const struct checkout_opts *opts,
 					fprintf(stderr, _("Can not do reflog for '%s': %s\n"),
 						opts->new_orphan_branch, err.buf);
 					strbuf_release(&err);
+					free(refname);
 					return;
 				}
 				strbuf_release(&err);