Multiple `mismatched-new-delete` warnings with gcc 11.3 and -Wall

[jsaf0]

When building latest master (53fded2) with gcc 11.3 (Ubuntu 22.04) and -Wall, the compiler complains about mismatched new-delete warnings. See snippet below:

/home/jfp/async/test/async_for.cpp: In function ‘boost::async::generator<int> test_data_gen()’:
/home/jfp/async/test/async_for.cpp:30:1: warning: ‘static void boost::async::promise_memory_resource_base::operator delete(void*, std::size_t)’ called on pointer returned from a mismatched allocation function [-Wmismatched-new-delete]
   30 | }

Is this warning safe to ignore?

[jsaf0]

FYI, gcc 13.0.1 does not give the same warnings.

[klemens-morgenstern]

From what I remember yes, but you might want to run the tests with the address sanitizer before using it in prod.

If this is an error (be it in the compiler), I can just remove the alloc-optimizations on that version.

[jsaf0]

No errors from building and running the unit tests with address sanitizer enabled - both on gcc 11.3.0 and gcc 13.0.1. So assume it's safe to ignore for now.

My previous comment from before that gcc 13.0.1 doesn't complain about mismatched-new-delete was not correct. When building in "debug mode" with CMake, it still spits out all these warnings. So it would definitely be nice to find a fix in order to avoid disabling this warning for all code.

[klemens-morgenstern]

I am pinning this because it'll come up again. This is safe, the gcc warnign is a false positive. It machtes the new & delete function signatures, and they don't match for coroutine allocations.

[MarekNiemiec]

I was able to reproduce -Wmismatched-new-delete via something like this:
awaitable<std::tuple<_,_,Config>>
Where Config is

struct Config{
...
std::array<Param,10>
...
}

Where Param is another struct(and another quite complex with some strings and another 2 structs inside.
Problem is only reproducible on our ci/cd
Commenting line with `std::array<Param,10> solves issue.
If I add Param param[10] issue.
If I change and add 10 separate Param structs no issue.
If I do std::array<int,10> no issue.

I can summarize it with problem appears if there is array/std::array with struct inside.
Struct itself is not a problem as I can do 10 structs inside(instead of array 10 elements).

We have gcc 14.2.
boost.asio 1.87
Visible only with -O2 -DNDEBUG

Just to remmind error:

[with Executor = boost::asio::any_io_executor]' called on pointer returned from a mismatched allocation function [-Werror=mismatched-new-delete]
<some not important data here>
/include/boost/asio/detail/memory.hpp:79:33: note: returned from 'void* aligned_alloc(size_t, size_t)'
   79 |   void* ptr = std::aligned_alloc(align, size);