This is to avoid an unnecessary multiple-choice menu for an
expression involving an enumeral declared in two types, when
the second type is an identical copy of the first type. This
happens in the following situation:
type Color is (Black, Red, Green, Blue, White);
type RGB_Color is new Color range Red .. Blue;
In that case, an implict type is created, and is used as the base
type for type RGB_Color. This base type is a copy of type Color.
We've added some extensive comments explaining the situation and
our approach further.
gdb/ChangeLog:
* ada-lang.c (ada_identical_enum_types_p): New function.
(symbols_are_identical_enums): New function.
(remove_extra_symbols): Do nothing if NSYMS < 2.
Use symbols_are_identical_enums.
gdb/testsuite/ChangeLog:
* gdb.ada/same_enum: New testcase.
