Fix resource leak found by Coverity
Commit Message
Hi all,
This commit fixes a resource leak found by Coverity where
find_oload_champ leaked every badness vector it calculated
bar the one it returned.
Built and regtested on RHEL 7.5 x86_64.
Ok to commit?
Thanks,
Gary
--
gdb/ChangeLog:
* valops.c (find_oload_champ): Fix resource leak found by
Coverity.
---
gdb/ChangeLog | 5 +++++
gdb/valops.c | 9 ++++++---
2 files changed, 11 insertions(+), 3 deletions(-)
Comments
Please use some more descriptive subject in these emails/commits,
otherwise we're going to end up with dozens of indistinct
"Fix resource leak found by Coverity" patches/emails. :-)
E.g., "Fix leak in valops.c:find_oload_champ" or some such.
As for the patch itself, I think that we'd still be leaking bv->rank,
right? Not just here, but in the callers of rank_function
as well?
I have a patch from last year here that converts the badness
vector to a C++ std::vector:
https://github.com/palves/gdb/commits/palves/badness_vector
See top two commits.
I guess a better approach would be to get that in instead.
Simon had a badness_vector C++ification patch too,
though his was different. ISTR that I prefer my approach,
but I won't be surprised if Simon preferred his. :-)
Thanks,
Pedro Alves
Pedro Alves wrote:
> Please use some more descriptive subject in these emails/commits,
> otherwise we're going to end up with dozens of indistinct
> "Fix resource leak found by Coverity" patches/emails. :-)
Yeah, it just occurred to me to do that, after I looked in my
inbox :D
> As for the patch itself, I think that we'd still be leaking
> bv->rank, right? Not just here, but in the callers of rank_function
> as well?
Oh, I just looked in valops.c to see what other things did to
free the vectors. So there's other leaks in there as well :/
> I have a patch from last year here that converts the badness
> vector to a C++ std::vector:
>
> https://github.com/palves/gdb/commits/palves/badness_vector
>
> See top two commits.
>
> I guess a better approach would be to get that in instead.
>
> Simon had a badness_vector C++ification patch too,
> though his was different. ISTR that I prefer my approach,
> but I won't be surprised if Simon preferred his. :-)
I'll look at them. Were they ever submitted, or unfinished, or... ?
Cheers,
Gary
@@ -3024,8 +3024,6 @@ find_oload_champ (struct value **args, int nargs,
struct badness_vector **oload_champ_bv)
{
int ix;
- /* A measure of how good an overloaded instance is. */
- struct badness_vector *bv;
/* Index of best overloaded function. */
int oload_champ = -1;
/* Current ambiguity state for overload resolution. */
@@ -3075,13 +3073,15 @@ find_oload_champ (struct value **args, int nargs,
/* Compare parameter types to supplied argument types. Skip
THIS for static methods. */
- bv = rank_function (parm_types, nparms,
+ struct badness_vector *bv
+ = rank_function (parm_types, nparms,
args + static_offset,
nargs - static_offset);
if (!*oload_champ_bv)
{
*oload_champ_bv = bv;
+ bv = NULL;
oload_champ = 0;
}
else /* See whether current candidate is better or worse than
@@ -3095,7 +3095,9 @@ find_oload_champ (struct value **args, int nargs,
oload_ambiguous = 2;
break;
case 2: /* New champion, record details. */
+ xfree (*oload_champ_bv);
*oload_champ_bv = bv;
+ bv = NULL;
oload_ambiguous = 0;
oload_champ = ix;
break;
@@ -3103,6 +3105,7 @@ find_oload_champ (struct value **args, int nargs,
default:
break;
}
+ xfree (bv);
xfree (parm_types);
if (overload_debug)
{