[Bug c++/100897] Symmetric transfer does not prevent stack-overflow for C++20 coroutines

["l.v.merzljak at gmail dot com" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100897

--- Comment #2 from Leonard von Merzljak <l.v.merzljak at gmail dot com> ---
(In reply to Iain Sandoe from comment #1)
> for symmetric transfer to work without stack overflow, it relies on an
> indirect tailcall.
> 
> For some GCC targets indirect tail-calls are not available without some
> additional support (see PR94794).
> 
> I tried to reproduce this (with a test case I use regularly for this) on a
> target that normally completes symmetric transfers successfully when the
> optimisation level is > 1. (x86_64, darwin).
> 
> The fail also occurs with my regular test case with -fsanitize=address - so,
> it seems that the inclusion of the address sanitiser is preventing or
> interfering with the tailcall.  Note that there are also other known issues
> with coroutines and the sanitizers (PR95137).

Thank you for your comment. I tried it out and can confirm that I don't get a
stack-overflow anymore if I omit -fsanitize=address and use an optimization
level > 1. If the issues with coroutines and sanitizers are already known, then
this bug report can be marked as resolved.
Of course, it would be nice if the stack-overflow would not occur even when
using an optimization level <= 1, but this probably does not qualify as a bug.