From 62e75a1f221947b4f5f8adba5992b68e6a0d3f42 Mon Sep 17 00:00:00 2001
From: Tyler Mandry <tmandry@gmail.com>
Date: Thu, 23 Jul 2020 17:41:05 -0700
Subject: [PATCH] Fix ICE while building MIR with type errors
Fixes #74047.
---
src/librustc_mir_build/hair/pattern/mod.rs | 5 -----
src/test/ui/issue-74047.rs | 17 +++++++++++++++++
src/test/ui/issue-74047.stderr | 12 ++++++++++++
3 files changed, 29 insertions(+), 5 deletions(-)
create mode 100644 src/test/ui/issue-74047.rs
create mode 100644 src/test/ui/issue-74047.stderr
diff --git a/src/librustc_mir_build/hair/pattern/mod.rs b/src/librustc_mir_build/hair/pattern/mod.rs
index 4fa23906a3568..a5c87bc963f49 100644
--- a/src/librustc_mir_build/hair/pattern/mod.rs
+++ b/src/librustc_mir_build/hair/pattern/mod.rs
@@ -509,11 +509,6 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> {
fn lower_pattern_unadjusted(&mut self, pat: &'tcx hir::Pat<'tcx>) -> Pat<'tcx> {
let mut ty = self.typeck_results.node_type(pat.hir_id);
- if let ty::Error(_) = ty.kind {
- // Avoid ICEs (e.g., #50577 and #50585).
- return Pat { span: pat.span, ty, kind: Box::new(PatKind::Wild) };
- }
-
let kind = match pat.kind {
hir::PatKind::Wild => PatKind::Wild,
diff --git a/src/test/ui/issue-74047.rs b/src/test/ui/issue-74047.rs
new file mode 100644
index 0000000000000..2e4f3e675c3b1
--- /dev/null
+++ b/src/test/ui/issue-74047.rs
@@ -0,0 +1,17 @@
+// edition:2018
+
+use std::convert::{TryFrom, TryInto};
+use std::io;
+
+pub struct MyStream;
+pub struct OtherStream;
+
+pub async fn connect() -> io::Result<MyStream> {
+ let stream: MyStream = OtherStream.try_into()?;
+ Ok(stream)
+}
+
+impl TryFrom<OtherStream> for MyStream {}
+//~^ ERROR: missing
+
+fn main() {}
diff --git a/src/test/ui/issue-74047.stderr b/src/test/ui/issue-74047.stderr
new file mode 100644
index 0000000000000..6f477c77cedbd
--- /dev/null
+++ b/src/test/ui/issue-74047.stderr
@@ -0,0 +1,12 @@
+error[E0046]: not all trait items implemented, missing: `Error`, `try_from`
+ --> $DIR/issue-74047.rs:14:1
+ |
+LL | impl TryFrom<OtherStream> for MyStream {}
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ missing `Error`, `try_from` in implementation
+ |
+ = help: implement the missing item: `type Error = Type;`
+ = help: implement the missing item: `fn try_from(_: T) -> std::result::Result<Self, <Self as std::convert::TryFrom<T>>::Error> { todo!() }`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0046`.