Dana Jansens 69ab97d716 Don't wrap an ErrorInst as a subpattern of another pattern (#5542) ...

When a pattern is an error, avoid wrapping it as a subpattern in a
RefParamPattern or VarPattern. This allows further error handling to
observe the error occurred without having to unwrap it.

This avoids a crash when an invalid associated constant is written which
has a VarPattern in it. The associated constant machinery expects an
AssociatedConstantDecl but was getting a VarPattern with an ErrorInst
inside. Now it receives an ErrorInst directly, which it is already
looking for.

This choice means that `var` statements in an `interface` will always be
diagnosed as being non-constant, or as being a constant with a `var`, so
we don't need an extra diagnostic saying that `var` is not allowed in an
interface, as this just leads to two diagnostics on the same thing.

This crash was found by a fuzzer.

2025-05-27 18:13:12 +00:00

..

min_prelude

Don't wrap an ErrorInst as a subpattern of another pattern (#5542)

2025-05-27 18:13:12 +00:00

no_prelude

Don't wrap an ErrorInst as a subpattern of another pattern (#5542)

2025-05-27 18:13:12 +00:00

fail_not_copyable.carbon

Improve lowering for global variables. (#5492)

2025-05-21 00:09:10 +00:00

fail_storage_is_literal.carbon

Improve lowering for global variables. (#5492)

2025-05-21 00:09:10 +00:00

fail_todo_control_flow_init.carbon

Adjust formatting of blocks and scopes (#5474)

2025-05-16 22:50:28 +00:00