686932 - incorrect valgrind annotation - accessing run->bin after VALGRIND_FREELIKE_BLOCK(run, 0);

Status: RESOLVED WONTFIX

(Core :: Memory Allocator, defect)

Description

[Igor Bukanov]

arena_dalloc_small from jemalloc.c contains, http://hg.mozilla.org/mozilla-central/file/f3f5d8a8a473/memory/jemalloc/jemalloc.c#l4212 ,

  4212 		VALGRIND_FREELIKE_BLOCK(run, 0);
  4213 		arena_run_dalloc(arena, run, true);

However, arena_run_dalloc dereferences run->bin at http://hg.mozilla.org/mozilla-central/file/f3f5d8a8a473/memory/jemalloc/jemalloc.c#l3393 leading to valgrind reporting an error when that line is reached. As far as I can see this is a regression from bug 446096.

Comment 1

[Igor Bukanov]

Attachment: v1

The patch moves VALGRIND_FREELIKE_BLOCK to arena_run_dalloc where it is called after run->bin access.

Comment 2

[Jason Evans]

I think either Nicholas Nethercote or Julian Seward re-did the valgrind support in jemalloc, so one of them would be a better reviewer for this.

Comment 3

[Igor Bukanov]

(In reply to Jason Evans from comment #2)
> I think either Nicholas Nethercote or Julian Seward re-did the valgrind
> support in jemalloc, so one of them would be a better reviewer for this.

Hm, hg log shows that the last valgrind-related changesets to jemalloc.c came from [e-mail] ;)

Comment 4

[Mike Hommey [:glandium]]

Bug 1057754 removed those annotations.