Remove "static item recursion checking" in favor of relying on cycle checks in the query engine

src/test/compile-fail/issue-17252.rs

@@ -8,12 +8,12 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-const FOO: usize = FOO; //~ ERROR recursive constant
+const FOO: usize = FOO; //~ ERROR E0391
 
 fn main() {
     let _x: [u8; FOO]; // caused stack overflow prior to fix
     let _y: usize = 1 + {
-        const BAR: usize = BAR; //~ ERROR recursive constant
+        const BAR: usize = BAR;
         let _z: [u8; BAR]; // caused stack overflow prior to fix
         1
     };

src/test/ui/issue-23302-1.rs

@@ -11,18 +11,7 @@
 // Check that an enum with recursion in the discriminant throws
 // the appropriate error (rather than, say, blowing the stack).
 enum X {
-    A = X::A as isize, //~ ERROR E0265
+    A = X::A as isize, //~ ERROR E0391
 }
 
-// Since `Y::B` here defaults to `Y::A+1`, this is also a
-// recursive definition.
-enum Y {
-    A = Y::B as isize, //~ ERROR E0265
-    B,
-}
-
-const A: i32 = B; //~ ERROR E0265
-
-const B: i32 = A; //~ ERROR E0265
-
 fn main() { }

src/test/ui/issue-23302-1.stderr

@@ -0,0 +1,15 @@
+error[E0391]: unsupported cyclic reference between types/traits detected
+  --> $DIR/issue-23302-1.rs:14:9
+   |
+14 |     A = X::A as isize, //~ ERROR E0391
+   |         ^^^^^^^^^^^^^ cyclic reference
+   |
+note: the cycle begins when const-evaluating `X::A::{{initializer}}`...
+  --> $DIR/issue-23302-1.rs:14:5
+   |
+14 |     A = X::A as isize, //~ ERROR E0391
+   |     ^^^^^^^^^^^^^^^^^
+   = note: ...which then again requires const-evaluating `X::A::{{initializer}}`, completing the cycle.
+
+error: aborting due to previous error
+

src/test/ui/issue-23302-2.rs

@@ -1,4 +1,4 @@
-// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.
 //
@@ -8,7 +8,11 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-const A: usize = B; //~ ERROR: recursive constant
-const B: usize = A; //~ ERROR: recursive constant
+// Since `Y::B` here defaults to `Y::A+1`, this is also a
+// recursive definition.
+enum Y {
+    A = Y::B as isize, //~ ERROR E0391
+    B,
+}
 
-fn main() {}
+fn main() { }

src/test/ui/issue-23302-2.stderr

@@ -0,0 +1,15 @@
+error[E0391]: unsupported cyclic reference between types/traits detected
+  --> $DIR/issue-23302-2.rs:14:9
+   |
+14 |     A = Y::B as isize, //~ ERROR E0391
+   |         ^^^^^^^^^^^^^ cyclic reference
+   |
+note: the cycle begins when const-evaluating `Y::A::{{initializer}}`...
+  --> $DIR/issue-23302-2.rs:14:5
+   |
+14 |     A = Y::B as isize, //~ ERROR E0391
+   |     ^^^^^^^^^^^^^^^^^
+   = note: ...which then again requires const-evaluating `Y::A::{{initializer}}`, completing the cycle.
+
+error: aborting due to previous error
+

src/test/ui/issue-23302-3.rs

@@ -1,4 +1,4 @@
-// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.
 //
@@ -8,8 +8,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-const a: isize = b; //~ ERROR recursive constant
-const b: isize = a; //~ ERROR recursive constant
+const A: i32 = B; //~ ERROR E0391
 
-fn main() {
-}
+const B: i32 = A;
+
+fn main() { }

src/test/ui/issue-23302-3.stderr

@@ -0,0 +1,20 @@
+error[E0391]: unsupported cyclic reference between types/traits detected
+  --> $DIR/issue-23302-3.rs:11:16
+   |
+11 | const A: i32 = B; //~ ERROR E0391
+   |                ^ cyclic reference
+   |
+note: the cycle begins when processing `B`...
+  --> $DIR/issue-23302-3.rs:13:1
+   |
+13 | const B: i32 = A;
+   | ^^^^^^^^^^^^^^^^^
+note: ...which then requires processing `A`...
+  --> $DIR/issue-23302-3.rs:13:16
+   |
+13 | const B: i32 = A;
+   |                ^
+   = note: ...which then again requires processing `B`, completing the cycle.
+
+error: aborting due to previous error
+

src/test/ui/issue-23302.stderr

@@ -1,26 +0,0 @@
-error[E0265]: recursive constant
-  --> $DIR/issue-23302.rs:14:9
-   |
-14 |     A = X::A as isize, //~ ERROR E0265
-   |         ^^^^^^^^^^^^^ recursion not allowed in constant
-
-error[E0265]: recursive constant
-  --> $DIR/issue-23302.rs:20:9
-   |
-20 |     A = Y::B as isize, //~ ERROR E0265
-   |         ^^^^^^^^^^^^^ recursion not allowed in constant
-
-error[E0265]: recursive constant
-  --> $DIR/issue-23302.rs:24:1
-   |
-24 | const A: i32 = B; //~ ERROR E0265
-   | ^^^^^^^^^^^^^^^^^ recursion not allowed in constant
-
-error[E0265]: recursive constant
-  --> $DIR/issue-23302.rs:26:1
-   |
-26 | const B: i32 = A; //~ ERROR E0265
-   | ^^^^^^^^^^^^^^^^^ recursion not allowed in constant
-
-error: aborting due to 4 previous errors
-

src/test/ui/issue-36163.rs

@@ -8,16 +8,10 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-const A: i32 = Foo::B; //~ ERROR E0265
+const A: isize = Foo::B as isize;
 
 enum Foo {
-    B = A, //~ ERROR E0265
+    B = A, //~ ERROR E0391
 }
 
-enum Bar {
-    C = Bar::C, //~ ERROR E0265
-}
-
-const D: i32 = A;
-
 fn main() {}

src/test/ui/issue-36163.stderr

@@ -1,20 +1,20 @@
-error[E0265]: recursive constant
-  --> $DIR/issue-36163.rs:11:1
-   |
-11 | const A: i32 = Foo::B; //~ ERROR E0265
-   | ^^^^^^^^^^^^^^^^^^^^^^ recursion not allowed in constant
-
-error[E0265]: recursive constant
+error[E0391]: unsupported cyclic reference between types/traits detected
   --> $DIR/issue-36163.rs:14:9
    |
-14 |     B = A, //~ ERROR E0265
-   |         ^ recursion not allowed in constant
-
-error[E0265]: recursive constant
-  --> $DIR/issue-36163.rs:18:9
+14 |     B = A, //~ ERROR E0391
+   |         ^ cyclic reference
    |
-18 |     C = Bar::C, //~ ERROR E0265
-   |         ^^^^^^ recursion not allowed in constant
+note: the cycle begins when const-evaluating `Foo::B::{{initializer}}`...
+  --> $DIR/issue-36163.rs:14:5
+   |
+14 |     B = A, //~ ERROR E0391
+   |     ^^^^^
+note: ...which then requires const-evaluating `A`...
+  --> $DIR/issue-36163.rs:14:9
+   |
+14 |     B = A, //~ ERROR E0391
+   |         ^
+   = note: ...which then again requires const-evaluating `Foo::B::{{initializer}}`, completing the cycle.
 
-error: aborting due to 3 previous errors
+error: aborting due to previous error