[patch] Backport of memleak fix to 0.12.x

[rsquires]

Backport of #481 to the 0.12.x line.

[sailsbot]

Hi @rsquires! It looks like the title of your pull request doesn’t quite match our guidelines yet. Would you please edit your pull request's title so that it begins with [proposal], [patch], [fixes #<issue number>], [implements #<other PR number>], or [misc]? Once you've edited it, I'll take another look!

[sailsbot]

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