c-decl.c overhaul (1/3) Refactor duplicate_decls

[Joseph S. Myers]

On Sun, 11 Jan 2004, Zack Weinberg wrote:

> it to be cured by patches 2 and 3 in this series.  If you can figure
> out some way to make gcc.dg test for the double error message that
> would be really cool.

There have been several duplicate message bugs before.  As far as I know
it would require hacking DejaGnu to support some way of detecting
duplicates or specifying exactly how many messages a particular line
should give matching a particular regexp.  (And if anyone is hacking core
DejaGnu like that for the benefit of GCC, I suspect making dg-warning and
dg-error mean what they say (distinguishing warnings from errors) would be
of substantial use for GCC.)

-- 
Joseph S. Myers
jsm@polyomino.org.uk