do_epoll_create failes with 'epoll: Function not supported".

[Oleg Grunin <oleg00@…>]

The relevant code: #if defined(EPOLL_CLOEXEC)

int fd = epoll_create1(EPOLL_CLOEXEC);

#else defined(EPOLL_CLOEXEC)

int fd = -1; errno = EINVAL;

#endif defined(EPOLL_CLOEXEC)

if (fd == -1 && errno == EINVAL) {

fd = epoll_create(epoll_size);

....

with glibc 2.13 EPOLL_CLOEXEC is always defined but epoll_create1 may return ENOSYS which causes the code below to fall though. The proposed patch is attached

[Oleg Grunin <oleg00@…>]

patch

[chris_kohlhoff]

(In [79521]) Add support for some newer versions of glibc which provide the epoll_create1 function but always fail with ENOSYS. Refs #7012

[chris_kohlhoff]

(In [79549]) Merge from trunk:

• Make strand destruction a no-op, to allow strand objects to be destroyed after their associated io_service has been destroyed.

• Use the thread keyword extension when compiling with gcc on linux x86.

• Avoid calling work_finished() if a completion handler creates more work.

• Eliminate redundant call to call_stack::contains(this) when dispatching a completion handler.

• Add support for some newer versions of glibc which provide the epoll_create1 function but always fail with ENOSYS. Fixes #7012

• Use SSE2 load and store fences.

• Throw exception if SSL engine initialisation fails. Fixes #6303

• Fix another regression in buffered_write_stream. Fixes #6310