[PATCH] Support thread cleanup without mingwm10.dll

[Aaron W. LaFramboise]

Brian Dessent wrote:
> "Aaron W. LaFramboise" wrote:
> 
>> This patch removes the requirement the -mthread be passed to link
>> against mingwm10.dll if multithreaded exceptions are desired.
> 
> The thing about using the PE static TLS callback is that it won't work
> for 9x/ME where the current method does.

OK, I did not realize this.  For some reason, I was pretty sure Win95 
supported it.  In that case, we'll need to do something to retain 
support for Win95 users.  I think it's still worth dropping mingwm10.dll 
and using libgcc_s_1.dll instead, but I will need to modify my patch 
slightly.

I'm going to look into this and post a revised patch.

> Also the documentation for -mthread should be updated to indicate that
> it no longer does anything and is only included for compatibility,
> preferably with a "will be removed in the future" type of wording.

OK, if noone has any strong feelings about retaining a 'singlethreaded 
mode' when GCC is built without --disable-threads, then I will update 
the documentation and make _MT always-on.