[PATCH] fortran/66044 -- Convert ICE into ordinary error

[FX]

> 2015-05-XX  Steven G. Kargl  <kargl@gcc.gnu.org>
> 
> 	PR fortran/66044
> 	* decl.c(gfc_match_entry):  Change a gfc_internal_error() into
> 	a gfc_error() 
> 
> 2015-05-XX  Steven G. Kargl  <kargl@gcc.gnu.org>
> 
> 	PR fortran/66044
> 	* gfortran.dg/entry_21.f90: New test.

OK