1 files changed, 215 insertions, 0 deletions
diff --git a/src/test/debuginfo/recursive-struct.rs b/src/test/debuginfo/recursive-struct.rs
new file mode 100644
index 000000000..eb14af8c5
--- /dev/null
+++ b/src/test/debuginfo/recursive-struct.rs
@@ -0,0 +1,215 @@
+// ignore-lldb
+
+// Require a gdb that can read DW_TAG_variant_part.
+// min-gdb-version: 8.2
+
+// compile-flags:-g
+
+// gdb-command:run
+
+// gdb-command:print stack_unique.value
+// gdb-check:$1 = 0
+// gdbr-command:print stack_unique.next.val.value
+// gdb-check:$2 = 1
+
+// gdbr-command:print unique_unique.value
+// gdb-check:$3 = 2
+// gdbr-command:print unique_unique.next.val.value
+// gdb-check:$4 = 3
+
+// gdb-command:print vec_unique[0].value
+// gdb-check:$5 = 6.5
+// gdbr-command:print vec_unique[0].next.val.value
+// gdb-check:$6 = 7.5
+
+// gdbr-command:print borrowed_unique.value
+// gdb-check:$7 = 8.5
+// gdbr-command:print borrowed_unique.next.val.value
+// gdb-check:$8 = 9.5
+
+// LONG CYCLE
+// gdb-command:print long_cycle1.value
+// gdb-check:$9 = 20
+// gdbr-command:print long_cycle1.next.value
+// gdb-check:$10 = 21
+// gdbr-command:print long_cycle1.next.next.value
+// gdb-check:$11 = 22
+// gdbr-command:print long_cycle1.next.next.next.value
+// gdb-check:$12 = 23
+
+// gdb-command:print long_cycle2.value
+// gdb-check:$13 = 24
+// gdbr-command:print long_cycle2.next.value
+// gdb-check:$14 = 25
+// gdbr-command:print long_cycle2.next.next.value
+// gdb-check:$15 = 26
+
+// gdb-command:print long_cycle3.value
+// gdb-check:$16 = 27
+// gdbr-command:print long_cycle3.next.value
+// gdb-check:$17 = 28
+
+// gdb-command:print long_cycle4.value
+// gdb-check:$18 = 29.5
+
+// gdbr-command:print long_cycle_w_anon_types.value
+// gdb-check:$19 = 30
+
+// gdbr-command:print long_cycle_w_anon_types.next.val.value
+// gdb-check:$20 = 31
+
+// gdb-command:continue
+
+#![allow(unused_variables)]
+#![feature(omit_gdb_pretty_printer_section)]
+#![omit_gdb_pretty_printer_section]
+
+use self::Opt::{Empty, Val};
+use std::boxed::Box as B;
+
+enum Opt<T> {
+    Empty,
+    Val { val: T }
+}
+
+struct UniqueNode<T> {
+    next: Opt<Box<UniqueNode<T>>>,
+    value: T
+}
+
+struct LongCycle1<T> {
+    next: Box<LongCycle2<T>>,
+    value: T,
+}
+
+struct LongCycle2<T> {
+    next: Box<LongCycle3<T>>,
+    value: T,
+}
+
+struct LongCycle3<T> {
+    next: Box<LongCycle4<T>>,
+    value: T,
+}
+
+struct LongCycle4<T> {
+    next: Option<Box<LongCycle1<T>>>,
+    value: T,
+}
+
+struct LongCycleWithAnonymousTypes {
+    next: Opt<Box<Box<Box<Box<Box<LongCycleWithAnonymousTypes>>>>>>,
+    value: usize,
+}
+
+// This test case makes sure that recursive structs are properly described. The Node structs are
+// generic so that we can have a new type (that newly needs to be described) for the different
+// cases. The potential problem with recursive types is that the DI generation algorithm gets
+// trapped in an endless loop. To make sure, we actually test this in the different cases, we have
+// to operate on a new type each time, otherwise we would just hit the DI cache for all but the
+// first case.
+
+// The different cases below (stack_*, unique_*, box_*, etc) are set up so that the type description
+// algorithm will enter the type reference cycle that is created by a recursive definition from a
+// different context each time.
+
+// The "long cycle" cases are constructed to span a longer, indirect recursion cycle between types.
+// The different locals will cause the DI algorithm to enter the type reference cycle at different
+// points.
+
+fn main() {
+    let stack_unique: UniqueNode<u16> = UniqueNode {
+        next: Val {
+            val: Box::new(UniqueNode {
+                next: Empty,
+                value: 1,
+            })
+        },
+        value: 0,
+    };
+
+    let unique_unique: Box<UniqueNode<u32>> = Box::new(UniqueNode {
+        next: Val {
+            val: Box::new(UniqueNode {
+                next: Empty,
+                value: 3,
+            })
+        },
+        value: 2,
+    });
+
+    let vec_unique: [UniqueNode<f32>; 1] = [UniqueNode {
+        next: Val {
+            val: Box::new(UniqueNode {
+                next: Empty,
+                value: 7.5,
+            })
+        },
+        value: 6.5,
+    }];
+
+    let borrowed_unique: &UniqueNode<f64> = &UniqueNode {
+        next: Val {
+            val: Box::new(UniqueNode {
+                next: Empty,
+                value: 9.5,
+            })
+        },
+        value: 8.5,
+    };
+
+    // LONG CYCLE
+    let long_cycle1: LongCycle1<u16> = LongCycle1 {
+        next: Box::new(LongCycle2 {
+            next: Box::new(LongCycle3 {
+                next: Box::new(LongCycle4 {
+                    next: None,
+                    value: 23,
+                }),
+                value: 22,
+            }),
+            value: 21
+        }),
+        value: 20
+    };
+
+    let long_cycle2: LongCycle2<u32> = LongCycle2 {
+        next: Box::new(LongCycle3 {
+            next: Box::new(LongCycle4 {
+                next: None,
+                value: 26,
+            }),
+            value: 25,
+        }),
+        value: 24
+    };
+
+    let long_cycle3: LongCycle3<u64> = LongCycle3 {
+        next: Box::new(LongCycle4 {
+            next: None,
+            value: 28,
+        }),
+        value: 27,
+    };
+
+    let long_cycle4: LongCycle4<f32> = LongCycle4 {
+        next: None,
+        value: 29.5,
+    };
+
+    // It's important that LongCycleWithAnonymousTypes is encountered only at the end of the
+    // `box` chain.
+    let long_cycle_w_anon_types = B::new(B::new(B::new(B::new(B::new(LongCycleWithAnonymousTypes {
+        next: Val {
+            val: Box::new(Box::new(Box::new(Box::new(Box::new(LongCycleWithAnonymousTypes {
+                next: Empty,
+                value: 31,
+            })))))
+        },
+        value: 30
+    })))));
+
+    zzz(); // #break
+}
+
+fn zzz() {()}