Issue #170: crashes occur indicating memory corruption, e.g. "double free".
This looks like a gcc compiler bug, probably this one.
These crashes seem to happen when co_await-ing an expression containing a (temporary) lambda taking a (string) argument by value.
The workaround would be to assign the lambda to a variable.
When there is a co_await on a lambda in the same function that creates the lambda, capturing by reference
should be safe: variables will disappear only after the co_await has finished.
Capturing by reference leads to smaller (and probably slightly faster) code.
Otherwise, capturing by value is needed, e.g. when the lambda is passed to make_shared_task_for_cacheable().