[C++] Avoid one place of frontend calling into targetm

[Steve Ellcey]

> > OK, In the mean time here is a bit more information, I think this is the
> > same as PR 31908 and may be related to PR 30151.  I just noticed while
> > looking around some more that while _GLOBAL__I_c went from being global
> > to being static, there is a new global variable called _GLOBAL__I_0_c
> > that wasn't there before.  _GLOBAL__I_0_c has a call to _GLOBAL__I_c, so
> > it looks like the bug is that the call from the code created by collect2
> > is using the static name, _GLOBAL__I_c, instead of the global name,
> > _GLOBAL__I_0_c.
> 
> It's probably trying to setup calls to both.  Don't think static variables
> should start with "_GLOBAL__".
> 
> Dave

You are right, when I look at the tmp file that gcc/collect2 use, I see
undefined references to _GLOBAL__I_0_c and _GLOBAL__I_c.

Steve Ellcey
sje@cup.hp.com