On 2/17/22 10:28, Stefan Hajnoczi wrote:
But going against ABI and toolchain in this way is really no long-term
solution. You need to switch to stackless co-routines, or we need to
provide proper ABI-level support for this. Today it's the thread
pointer, tomorrow it's the shadow stack pointer, and the day after that,
it's the SafeStack pointer. And further down the road, it's some thread
state for garbage collection support. Or something like that.
Yes, understood :(. This does feel like solving an undefined behavior
problem by adding more undefined behavior on top!
Yes, this is the kind of thing that I generally despise when I see other
programs do it... it's easy to dig ourselves in the same hole.
I took a quick look at C++20 coroutines since they are available in
compilers but the primitives look hard to use even from C++, let alone
from C.
They're C++ only in GCC, too. I really think that QEMU should be
compilable in C++, but I'm not sure how easy a sell it is.
Paolo
