Loc will be updated once we encounter the definition

When using an enum in a ternary operator, the value is const-folded
before checking if it evaluates to `true` or `false` so that const-expr
used as enum values are supported.

- since we rename builtin labels, let us just try to find a label that does not need renaming

Allan Blanchard authored 1 year ago and Virgile Prevosto committed 11 months ago

- guarantee that pp code has the same semantics in such a case