On Tue, 21 May 2024, Martin Uecker wrote: > > The constraint violated is the general one "If an identifier has no > > linkage, there shall be no more than one declaration of the identifier (in > > a declarator or type specifier) with the same scope and in the same name > > space, except that: ... enumeration constants and tags may be redeclared > > as specified in 6.7.3.3 and 6.7.3.4, respectively." (where 6.7.3.3 says > > "Enumeration constants can be redefined in the same scope with the same > > value as part of a redeclaration of the same enumerated type." - as the > > redefinition is not with the same value, the "as specified in 6.7.3.3" is > > not satisfied and so the general constraint against redeclarations with no > > linkage applies). > > This assumes that the value in question is the one of the initializer and not > the > one after initialization (with no clear rules how this works in this case),
There are no initializers here. The constant-expression after '=' in the syntax for enumerator is not an initializer, and none of the rules for initializers apply to it. (If the initializer with an out-of-range value also gets used in an expression, the constraint on constants would be violated, "Each constant shall have a type and the value of a constant shall be in the range of representable values for its type." - but the constraint on multiple declarations applies whether it's used or not.) -- Joseph S. Myers josmy...@redhat.com
