Unit Tests failing when built with clang 12

[Stephan Bergmann]

On 15/03/2021 20:54, Luke Benes wrote:
> The  recently added Unit Test test_tdf131000
> https://cgit.freedesktop.org/libreoffice/core/commit/?id=df33714f0eca
> fails with clang 12 but not with gcc 10 or clang 11. I bisected this regression to this change in clang:
> 
> https://github.com/llvm/llvm-project/commit/69cd776e1ee79e72ccbdad30749eac04579715ee
>      [CodeGen] Apply 'nonnull' and 'dereferenceable(N)' to 'this' pointer
> 
> 
> Does this look like undefined behavior on our end or a bug in clang? The build log is below:

Interesting.  I can't reproduce that UITest_calc_tests9 SEGV with any of 
my Clang 13 trunk builds (which also include the above LLVM commit), but 
they're all --enable-dbgutil (and thus implicitly --disable-optimized), 
while your build is presumably (implicitly) --enable-optimized?