mlugg 107b65ec5d Sema: explain why we tried to call an extern fn at comptime
I recently saw a user hit the "comptime call of extern function" error,
and get confused because they didn't know why the scope was `comptime`.
So, use `explainWhyBlockIsComptime` on this and related errors to add
all the relevant notes.

The added test case shows the motivating situation.
2025-01-29 18:43:24 +00:00
..
2025-01-16 20:42:08 -05:00
2024-03-28 15:24:01 +02:00