bug#37852: Build failure on MSYS2 (undefined reference to _chk functions)

[Eli Zaretskii]

> From: Richard Copley <rcopley@gmail.com>
> Date: Mon, 21 Oct 2019 14:17:36 +0100
> Cc: 37852@debbugs.gnu.org
> 
> On Mon, 21 Oct 2019 at 14:07, Eli Zaretskii <eliz@gnu.org> wrote:
> 
>  > From: Richard Copley <rcopley@gmail.com>
>  > Date: Mon, 21 Oct 2019 13:28:29 +0100
>  > 
>  > Linking auxiliary executables fails with undefined references to 
> (FORTIFY_SOURCE?) functions 
>  > __memcpy_chk and __memmove_chk. This is apparently caused by some change 
> in MSYS2,
>  because
>  > previously buildable commits now fail. Transcript below.
> 
>  Looks like FORTIFY_SOURCE requires linking against -lssp?  Can you try
>  adding that, e.g. by
> 
>    make LIBS_SYSTEM=-lssp
> 
> Yes, that works.

OK, thanks.

So do we need to add that library to the link command under some
conditions?  IOW, is FORTIFY_SOURCE something that comes out of our
configure script (in which case I'm missing something, because I
didn't find it in the configure script), or is this an option you
added manually?  In the latter case, would configuring with LIBS=-lssp
be an okay solution?