const_eval_checked: deal with unused nodes + div

src/test/ui/const-generics/const_evaluatable_checked/division.rs

@@ -0,0 +1,11 @@
+// run-pass
+#![feature(const_generics, const_evaluatable_checked)]
+#![allow(incomplete_features)]
+
+fn with_bound<const N: usize>() where [u8; N / 2]: Sized {
+    let _: [u8; N / 2] = [0; N / 2];
+}
+
+fn main() {
+    with_bound::<4>();
+}

src/test/ui/const-generics/const_evaluatable_checked/unused_expr.rs

@@ -0,0 +1,25 @@
+#![feature(const_generics, const_evaluatable_checked)]
+#![allow(incomplete_features)]
+
+fn add<const N: usize>() -> [u8; { N + 1; 5 }] {
+    //~^ ERROR overly complex generic constant
+    todo!()
+}
+
+fn div<const N: usize>() -> [u8; { N / 1; 5 }] {
+    //~^ ERROR overly complex generic constant
+    todo!()
+}
+
+const fn foo(n: usize) {}
+
+fn fn_call<const N: usize>() -> [u8; { foo(N); 5 }] {
+    //~^ ERROR overly complex generic constant
+    todo!()
+}
+
+fn main() {
+    add::<12>();
+    div::<9>();
+    fn_call::<14>();
+}

src/test/ui/const-generics/const_evaluatable_checked/unused_expr.stderr

@@ -0,0 +1,26 @@
+error: overly complex generic constant
+  --> $DIR/unused_expr.rs:4:34
+   |
+LL | fn add<const N: usize>() -> [u8; { N + 1; 5 }] {
+   |                                  ^^^^^^^^^^^^ unused node
+   |
+   = help: consider moving this anonymous constant into a `const` function
+
+error: overly complex generic constant
+  --> $DIR/unused_expr.rs:9:34
+   |
+LL | fn div<const N: usize>() -> [u8; { N / 1; 5 }] {
+   |                                  ^^^^^^^^^^^^ unused node
+   |
+   = help: consider moving this anonymous constant into a `const` function
+
+error: overly complex generic constant
+  --> $DIR/unused_expr.rs:16:38
+   |
+LL | fn fn_call<const N: usize>() -> [u8; { foo(N); 5 }] {
+   |                                      ^^^^^^^^^^^^^ unused node
+   |
+   = help: consider moving this anonymous constant into a `const` function
+
+error: aborting due to 3 previous errors
+