...where "make ... debug=t" is used to build some parts of LO with debug enabled
without re-running autogen.sh (so NDEBUG will start to be undefined, so
constexpr functions calling assert will start to trigger GCC PR66460).  See mail
thread starting at
<https://lists.freedesktop.org/archives/libreoffice/2016-March/073554.html>
"Compiler crash when building libreoffice with debug."

Change-Id: I6e3c0375c1e5843616fb9fe287d0bf5ee40e64f7