This also prevents an invalid memory access: we were storing the pointer
to a temporary in the struct and then using it after temporary was gone.

Change-Id: I2b6d9df16bc24b222095ccbf45c9f0bd9c86ed65
(cherry picked from commit 9d2e0d60)
Reviewed-on: https://gerrit.libreoffice.org/46949Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>