969133 - OdinMonkey: Valgrind detects leak - 96 bytes are definitely lost (direct) with GrowStuff on the stack

Status: RESOLVED FIXED

(Core :: JavaScript Engine: JIT, defect)

Description

[Gary Kwong [:gkw] [:nth10sd] (NOT official MoCo now)]

Attachment: Valgrind stack with --vex-iropt-register-updates=allregs-at-mem-access

+++ This bug was initially created as a clone of Bug #913876 +++

(function(stdlib, foreign, heap) {
    "use asm";
    var Float64ArrayView = new stdlib.Float64Array(heap);
    function f() {}
    return f
})(this, {}, new ArrayBuffer())

shows "96 bytes in 1 blocks are definitely lost" on m-c changeset 1e9f169c9715 with --no-baseline --ion-parallel-compile=off --no-ion.

valgrind --vex-iropt-register-updates=allregs-at-mem-access --leak-check=full --smc-check=all-non-file ./js-opt-64-dm-vg-ts-er-linux-1e9f169c9715 --no-baseline --ion-parallel-compile=off --no-ion testcase.js

(happens also with --vex-iropt-register-updates=allregs-at-each-insn)


Is this another false positive, as per bug 913876?

My configure flags are:

AR=ar sh ./configure --enable-optimize=-O1 --disable-debug --enable-profiling --enable-gczeal --enable-debug-symbols --enable-methodjit --enable-type-inference --disable-tests --enable-more-deterministic --enable-exact-rooting --enable-valgrind --with-ccache --enable-threadsafe <other NSPR options>

Comment 1

[Nicholas Nethercote [inactive]]

> Is this another false positive, as per bug 913876?

That was an invalid write, but this is a leak. I doubt it's a false positive.

Comment 2

[Luke Wagner [:luke]]

Yep, definitely real.  Looks like bug 865516 and bug 917800 introduced the leak by passing JS_smprintf results to LinkFail, which only expects string literals and doesn't free.  Easy fix, though.

Comment 3

[Luke Wagner [:luke]]

Attachment: fix-leak

Comment 4

[Benjamin Bouvier [:bbouvier] (inactive)]

Comment on attachment 8372313 [details] [diff] [review]
fix-leak

Review of attachment 8372313 [details] [diff] [review]:
-----------------------------------------------------------------

Nice catch, thanks!

Comment 5

[Luke Wagner [:luke]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/be7fa3989aed

Comment 6

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/be7fa3989aed