Re: [pushed] Fix struct sockaddr/sockaddr_in/sockaddr_un strict aliasing violations

[Eli Zaretskii <eliz@gnu.org>]

> From: Pedro Alves <palves@redhat.com>
> Date: Sat,  7 Mar 2015 17:44:26 +0000
> 
> Building gdbserver in C++ mode shows:
> 
>   gdb/gdbserver/tracepoint.c: In function ‘void* gdb_agent_helper_thread(void*)’:
>   gdb/gdbserver/tracepoint.c:7190:47: error: cannot convert ‘sockaddr_un*’ to ‘sockaddr*’ for argument ‘2’ to ‘int accept(int, sockaddr*, socklen_t*)’
> 	  fd = accept (listen_fd, &sockaddr, &tmp);
> 
> A few places in the tree already have an explicit cast to struct
> sockaddr *, but that's a strict aliasing violation.  Instead of
> propagating invalid code, fix this by using a union instead.

Yuck!  Isn't there a better way?  Why do we have the original problem
to begin with, i.e. where did the incompatible data type come from?

(Does it even make sense to work around C++ restrictions while
converting code to C++?)

Thanks.