[Issue 23396] New: [std.socket] getAddresses causes TcpSocket to open UDP sockets first

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=23396

          Issue ID: 23396
           Summary: [std.socket] getAddresses causes TcpSocket to open UDP
                    sockets first
           Product: D
           Version: D2
          Hardware: All
               URL: http://dlang.org/phobos/
                OS: Linux
            Status: NEW
          Severity: major
          Priority: P3
         Component: phobos
          Assignee: nobody at puremagic.com
          Reporter: witold.baryluk+d at gmail.com

Linux amd64. Debian testing.

Verified on:

- dmd 2.100.2-0
- gdc 12.2.0
- gdc 10.2.1-6

Also I got it sporadically when using:

- ldc2 1:1.30.0-1+b1 (based on DMD v2.100.1 and LLVM 14.0.6)



```
void main() {
  import std;
  auto addresses = getAddress("www.google.com", 3333);
  auto sock = new TcpSocket(addresses[0]);
}
```


running under strace:


```
$ strace -e close,socket,connect,getsockname ./a.out >/dev/null
...
socket(AF_INET6, SOCK_DGRAM|SOCK_CLOEXEC, IPPROTO_IP) = 3
connect(3, {sa_family=AF_INET6, sin6_port=htons(3333), sin6_flowinfo=htonl(0),
inet_pton(AF_INET6, "2a00:1450:400a:801::2004", &sin6_addr), sin6_scope_id=0},
28) = 0
getsockname(3, {sa_family=AF_INET6, sin6_port=htons(36873),
sin6_flowinfo=htonl(0), inet_pton(AF_INET6, "2a02:REDACTED", &sin6_addr),
sin6_scope_id=0}, [28]) = 0
connect(3, {sa_family=AF_UNSPEC, sa_data="\0\0\0\0\0\0\0\0\0\0\0\0\0\0"}, 16) =
0
connect(3, {sa_family=AF_INET, sin_port=htons(3333),
sin_addr=inet_addr("142.250.203.100")}, 16) = 0
getsockname(3, {sa_family=AF_INET6, sin6_port=htons(49645),
sin6_flowinfo=htonl(0), inet_pton(AF_INET6, "::ffff:10.0.0.READACTED",
&sin6_addr), sin6_scope_id=0}, [28]) = 0
close(3)                                = 0
socket(AF_INET6, SOCK_STREAM, IPPROTO_TCP) = 3
connect(3, {sa_family=AF_INET6, sin6_port=htons(3333), sin6_flowinfo=htonl(0),
inet_pton(AF_INET6, "2a00:1450:400a:801::2004", &sin6_addr), sin6_scope_id=0},
28

```

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