问题
Can anyone give me an example of how I can use segmented stacks with boost coroutines? Do I have to annotate every function that is called from the coroutine with a special split-stack
attribute?
When I try and write a program that should use segmented stacks, it just segfaults.
Here is what I have done so far https://wandbox.org/permlink/TltQwGpy4hRoHgDY The code seems to segfault very quickly, if segmented stacks were used I would expect it to be able to handle more iterations. The program errors out after 35 iterations.
#include <boost/coroutine2/all.hpp>
#include <iostream>
#include <array>
using std::cout;
using std::endl;
class Int {
int a{2};
};
void foo(int num) {
cout << "In iteration " << num << endl;
std::array<Int, 1000> arr;
static_cast<void>(arr);
foo(num + 1);
}
int main() {
using Coroutine_t = boost::coroutines2::coroutine<int>::push_type;
auto coro = Coroutine_t{[&](auto& yield) {
foo(yield.get());
}};
coro(0);
}
回答1:
Compiling that code with -fsplit-stack
solves the problem. Annotations are not required. All functions are by default treated as split stacks. Example - https://wandbox.org/permlink/Pzzj5gMoUAyU0h7Q
Easy as that.
回答2:
compile boost (boost.context and boost.coroutine) with b2 property segmented-stacks=on (enables special code inside boost.coroutine and boost.context).
your app has to be compiled with -DBOOST_USE_SEGMENTED_STACKS
and -fsplit-stack
(required by boost.coroutines headers).
see documentation: http://www.boost.org/doc/libs/1_65_1/libs/coroutine/doc/html/coroutine/stack/segmented_stack_allocator.html
boost.coroutine contains an example that demonstrates segmented stacks
(in directory coroutine/example/asymmetric/ call b2 toolset=gcc segmented-stacks=on
).
please note: while llvm supports segmented stacks, clang seams not to provide the __splitstack_<xyz>
functions.
来源:https://stackoverflow.com/questions/46286379/boost-coroutine-not-using-segmented-stacks