OPT_NOREPLY: touch() stuck forever

[killerbees19]

Example code:

<?php

$mc = new Memcached();
$mc->addServer('localhost', 11211);
$mc->setOptions([Memcached::OPT_NOREPLY => true]);
$mc->touch('test', 120);

Now it's stuck at 100% CPU usage until the process gets killed. Without OPT_NOREPLY everything is fine. Both protocols (text/binary) are affected by this bug.

strace output:

connect(3, {sa_family=AF_INET, sin_port=htons(11211), sin_addr=inet_addr("127.0.0.1")}, 16) = -1 EINPROGRESS (Operation now in progress)
poll([{fd=3, events=POLLOUT}], 1, 4000) = 1 ([{fd=3, revents=POLLOUT}])
getsockopt(3, SOL_SOCKET, SO_ERROR, [0], [4]) = 0
sendto(3, "touch test 120\r\n", 16, MSG_NOSIGNAL, NULL, 0) = 16
recvfrom(3, "NOT_FOUND\r\n", 8196, MSG_NOSIGNAL, NULL, NULL) = 11
write(1, "bool(true)\n", 11bool(true)
)            = 11
write(1, "bool(false)\n", 12bool(false)
)           = 12
sendto(3, "quit\r\n", 6, MSG_NOSIGNAL, NULL, 0) = 6
recvfrom(3, "", 8196, MSG_NOSIGNAL, NULL, NULL) = 0
shutdown(3, SHUT_RDWR)                  = 0
close(3)                                = 0

connect(3, {sa_family=AF_INET, sin_port=htons(11211), sin_addr=inet_addr("127.0.0.1")}, 16) = -1 EINPROGRESS (Operation now in progress)
poll([{fd=3, events=POLLOUT}], 1, 4000) = 1 ([{fd=3, revents=POLLOUT}])
getsockopt(3, SOL_SOCKET, SO_ERROR, [0], [4]) = 0
sendto(3, "\200\34\0\4\4\0\0\0\0\0\0\10\0\1\0\0\0\0\0\0\0\0\0\0\0\0\0xtest", 32, MSG_NOSIGNAL, NULL, 0) = 32
recvfrom(3, "\201\34\0\0\0\0\0\1\0\0\0\t\0\1\0\0\0\0\0\0\0\0\0\0Not foun"..., 8196, MSG_NOSIGNAL, NULL, NULL) = 33
write(1, "bool(true)\n", 11bool(true)
)            = 11
write(1, "bool(false)\n", 12bool(false)
)           = 12
sendto(3, "\200\7\0\0\0\0\0\0\0\0\0\0\0\2\0\0\0\0\0\0\0\0\0\0", 24, MSG_NOSIGNAL, NULL, 0) = 24
recvfrom(3, "\201\7\0\0\0\0\0\0\0\0\0\0\0\2\0\0\0\0\0\0\0\0\0\0", 8196, MSG_NOSIGNAL, NULL, NULL) = 24
recvfrom(3, "", 8196, MSG_NOSIGNAL, NULL, NULL) = 0
shutdown(3, SHUT_RDWR)                  = 0
close(3)                                = 0

Tested at Debian 11 (amd64) with PHP 5.6 to 8.2 (deb.sury.org)

libmemcached11       1.0.18-4.2                                  
php5.6-memcached     1:2.2.0-1+0~20230619.3+debian11~1.gbpaf2604 
php7.0-memcached     3.2.0++-1+0~20230622.54+debian11~1.gbp8f3995
php7.1-memcached     3.2.0++-1+0~20230622.54+debian11~1.gbp8f3995
php7.2-memcached     3.2.0++-1+0~20230622.54+debian11~1.gbp8f3995
php7.3-memcached     3.2.0++-1+0~20230622.54+debian11~1.gbp8f3995
php7.4-memcached     3.2.0++-1+0~20230622.54+debian11~1.gbp8f3995
php8.0-memcached     3.2.0++-1+0~20230622.54+debian11~1.gbp8f3995
php8.1-memcached     3.2.0++-1+0~20230622.54+debian11~1.gbp8f3995
php8.2-memcached     3.2.0++-1+0~20230622.54+debian11~1.gbp8f3995