On 2016-05-05 09:32, Fabien COELHO wrote:
>> I note that C99 specifically mentions this as something a compiler
>> might warn about: [...]
>
> Indeed. Neither gcc nor clang emit such warnings... but they might some
> day, which would be a blow for my suggestion!
For what it's worth, newer versions of clang can emit useful warnings
for cases like this:
int main(void) {enum test { FOUR = 4 };enum incompatible { INCOMPATIBLE_FOUR = 4 };enum test variable;variable =
INCOMPATIBLE_FOUR;variable= 5;variable = 4;variable = 3;return 0;
}
enum.c:5:13: warning: implicit conversion from enumeration type 'enum
incompatible' to different enumeration type 'enum test' [-Wenum-conversion] variable = INCOMPATIBLE_FOUR;
~ ^~~~~~~~~~~~~~~~~
enum.c:6:13: warning: integer constant not in range of enumerated type
'enum test' [-Wassign-enum] variable = 5; ^
enum.c:8:13: warning: integer constant not in range of enumerated type
'enum test' [-Wassign-enum] variable = 3; ^
3 warnings generated.
So with -Wenum-conversion -Wassign-enum you could treat enum types as
distinct and incompatible with each other.
