Catch overflow early

3 files changed, 39 insertions, 2 deletions

diff --git a/src/test/ui/recursion/issue-83150.stderr b/src/test/ui/recursion/issue-83150.stderr
index 07f82847568..ea49e82ac7a 100644
--- a/src/test/ui/recursion/issue-83150.stderr
+++ b/src/test/ui/recursion/issue-83150.stderr
@@ -9,10 +9,12 @@ LL |     func(&mut iter.map(|x| x + 1))
    = note: `#[warn(unconditional_recursion)]` on by default
    = help: a `loop` may express intention better if this is on purpose
 
-error[E0275]: overflow evaluating the requirement `Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut std::ops::Range<u8>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>: Iterator`
+error[E0275]: overflow evaluating the requirement `<std::ops::Range<u8> as Iterator>::Item`
    |
    = help: consider increasing the recursion limit by adding a `#![recursion_limit = "256"]` attribute to your crate (`issue_83150`)
-   = note: required for `&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut std::ops::Range<u8>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>` to implement `Iterator`
+   = note: required because of the requirements on the impl of `Iterator` for `Map<&mut std::ops::Range<u8>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>`
+   = note: 64 redundant requirements hidden
+   = note: required because of the requirements on the impl of `Iterator` for `&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut std::ops::Range<u8>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>, [closure@$DIR/issue-83150.rs:11:24: 11:27]>`
 
 error: aborting due to previous error; 1 warning emitted
 
diff --git a/src/test/ui/recursion/issue-95134.rs b/src/test/ui/recursion/issue-95134.rs
new file mode 100644
index 00000000000..adc9c6ee2d9
--- /dev/null
+++ b/src/test/ui/recursion/issue-95134.rs
@@ -0,0 +1,28 @@
+// build-fail
+// compile-flags: -Copt-level=0
+//~^^ ERROR overflow evaluating the requirement
+
+pub fn encode_num<Writer: ExampleWriter>(n: u32, mut writer: Writer) -> Result<(), Writer::Error> {
+    if n > 15 {
+        encode_num(n / 16, &mut writer)?;
+    }
+    Ok(())
+}
+
+pub trait ExampleWriter {
+    type Error;
+}
+
+impl<'a, T: ExampleWriter> ExampleWriter for &'a mut T {
+    type Error = T::Error;
+}
+
+struct EmptyWriter;
+
+impl ExampleWriter for EmptyWriter {
+    type Error = ();
+}
+
+fn main() {
+    encode_num(69, &mut EmptyWriter).unwrap();
+}
diff --git a/src/test/ui/recursion/issue-95134.stderr b/src/test/ui/recursion/issue-95134.stderr
new file mode 100644
index 00000000000..57a498694b7
--- /dev/null
+++ b/src/test/ui/recursion/issue-95134.stderr
@@ -0,0 +1,7 @@
+error[E0275]: overflow evaluating the requirement `<EmptyWriter as ExampleWriter>::Error`
+   |
+   = help: consider increasing the recursion limit by adding a `#![recursion_limit = "256"]` attribute to your crate (`issue_95134`)
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0275`.