https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121052
--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Jonathan Wakely from comment #0)
> Many of our uses of the nonnull attribute are probably bugs, e.g.
>
> polymorphic_allocator(memory_resource* __r) noexcept
> __attribute__((__nonnull__))
> : _M_resource(__r)
> { _GLIBCXX_DEBUG_ASSERT(__r); }
>
> This debug assertion never fails in optimized builds, because the nonnull
> attribute tells the compiler that __r is not null, so the assertion is
> optimized out as dead code.
Maybe my thinking here was that builds using _GLIBCXX_DEBUG are more likely to
be done with -O0 and in that case, the attribute would not remove the
assertion. So it can still find bugs in user code sometimes.
