...for whatever reason.  Failure is

> AddressSanitizer:DEADLYSIGNAL
> =================================================================
> ==16438==ERROR: AddressSanitizer: SEGV on unknown address 0x000000000000 (pc 0x2b6ba8bfe65c bp 0x7ffca100f290 sp 0x7ffca100ba28 T0)
> ==16438==The signal is caused by a READ memory access.
> ==16438==Hint: address points to the zero page.
>     #0 0x2b6ba8bfe65b  (<unknown module>)
>
> AddressSanitizer can not provide additional info.
> SUMMARY: AddressSanitizer: SEGV (<unknown module>)
> ==16438==ABORTING
> /home/tdf/lode/jenkins/workspace/lo_ubsan/testtools/CustomTarget_uno_test.mk:25: recipe for target '/home/tdf/lode/jenkins/workspace/lo_ubsan/workdir/CustomTarget/testtools/uno_test.done' failed

(<https://ci.libreoffice.org/job/lo_ubsan/1177/>, but also seen with local ASan+
UBSan builds.)

Started to fail with 98f5f97d "make --enable-ld
the default for debug builds, if available".  (lld would automatically be
disabled by configure.ac because it doesn't support --dynamic-list-cpp-typeinfo
as needed by UBSan.)

Change-Id: I7bfbfc4c879cbad7748e5855c22698eec5efc94c