[BUG]: segfault with HPC SDK 23.7
gonzalobg opened this issue · comments
Reproducer:
#if 0
set -ex
nvc++ -std=c++20 --experimental-stdpar -stdpar -o bug $0
./bug
exit 0
#endif
#include <algorithm>
#include <execution>
#include <iostream>
#include <stdexec/execution.hpp>
#include <exec/static_thread_pool.hpp>
#include <nvexec/stream_context.cuh>
#include <exec/inline_scheduler.hpp>
int main() {
auto gpu_ctx = nvexec::stream_context{};
auto cpu_ctx = exec::static_thread_pool{1}; // exec::inline_scheduler{};
auto sg = gpu_ctx.get_scheduler();
auto sc = cpu_ctx.get_scheduler();
std::vector<int> v;
v.push_back(0);
auto t = stdexec::schedule(sg)
| stdexec::bulk(1, [v = v.data()](int i) { v[0] = 1; })
| stdexec::bulk(1, [v = v.data()](int i) { v[0] += 1; })
| stdexec::transfer(sc) | stdexec::then([v = v.data()] { v[0] += 1;})
| stdexec::transfer(sg) | stdexec::bulk(1, [v = v.data()](int i) { v[0] += 1; })
| stdexec::transfer(sc) | stdexec::then([v = v.data()] { v[0] += 1;})
| stdexec::transfer(sg) | stdexec::bulk(1, [v = v.data()](int i) { v[0] += 1; })
;
stdexec::sync_wait(std::move(t));
if (v[0] == 6) {
std::cerr << "Success!" << std::endl;
return 0;
}
std::cerr << "Failed: " << v[0] << std::endl;
return 1;
} 
I can reproduce the crash with the HPC SDK 23.7.
The --experimenal-stdpar flag makes the compiler use the version of stdexec that shipped with the SDK. If, however, I remove that flag and instead point the build at the latest version of stdexec from main, the the program runs successfully for me.
@gonzalobg can you confirm? closing this for now.