Make effects an incomplete feature

Author: fee1-dead

tests/ui/rfcs/rfc-2632-const-trait-impl/call-generic-method-fail.rs

@@ -1,6 +1,6 @@
 //@ check-pass
 
-#![feature(const_trait_impl, effects)]
+#![feature(const_trait_impl, effects)] //~ WARN the feature `effects` is incomplete
 
 pub const fn equals_self<T: PartialEq>(t: &T) -> bool {
     *t == *t

tests/ui/rfcs/rfc-2632-const-trait-impl/call-generic-method-fail.stderr

@@ -0,0 +1,11 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/call-generic-method-fail.rs:3:30
+   |
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
+warning: 1 warning emitted
+

tests/ui/rfcs/rfc-2632-const-trait-impl/call-generic-method-nonconst.rs

@@ -1,4 +1,4 @@
-#![feature(const_trait_impl, effects)]
+#![feature(const_trait_impl, effects)] //~ WARN the feature `effects` is incomplete
 
 struct S;