From ae85bbb2d180fd73631ee4d44c41c8225b923df2 Mon Sep 17 00:00:00 2001
From: Bastian Kauschke <bastian_kauschke@hotmail.de>
Date: Fri, 11 Sep 2020 18:39:26 +0200
Subject: [PATCH] do not ICE on `ty::Bound` in Layout::compute

---
 compiler/rustc_middle/src/ty/layout.rs        |  4 ++--
 .../ui/const-generics/issues/issue-76595.rs   | 18 ++++++++++++++++
 .../const-generics/issues/issue-76595.stderr  | 21 +++++++++++++++++++
 3 files changed, 41 insertions(+), 2 deletions(-)
 create mode 100644 src/test/ui/const-generics/issues/issue-76595.rs
 create mode 100644 src/test/ui/const-generics/issues/issue-76595.stderr

diff --git a/compiler/rustc_middle/src/ty/layout.rs b/compiler/rustc_middle/src/ty/layout.rs
index b0a1413a9d62f..cb79b089d94a0 100644
--- a/compiler/rustc_middle/src/ty/layout.rs
+++ b/compiler/rustc_middle/src/ty/layout.rs
@@ -1259,11 +1259,11 @@ impl<'tcx> LayoutCx<'tcx, TyCtxt<'tcx>> {
                 tcx.layout_raw(param_env.and(normalized))?
             }
 
-            ty::Bound(..) | ty::Placeholder(..) | ty::GeneratorWitness(..) | ty::Infer(_) => {
+            ty::Placeholder(..) | ty::GeneratorWitness(..) | ty::Infer(_) => {
                 bug!("Layout::compute: unexpected type `{}`", ty)
             }
 
-            ty::Param(_) | ty::Error(_) => {
+            ty::Bound(..) | ty::Param(_) | ty::Error(_) => {
                 return Err(LayoutError::Unknown(ty));
             }
         })
diff --git a/src/test/ui/const-generics/issues/issue-76595.rs b/src/test/ui/const-generics/issues/issue-76595.rs
new file mode 100644
index 0000000000000..0a16ca181f557
--- /dev/null
+++ b/src/test/ui/const-generics/issues/issue-76595.rs
@@ -0,0 +1,18 @@
+#![feature(const_generics, const_evaluatable_checked)]
+#![allow(incomplete_features)]
+
+struct Bool<const B: bool>;
+
+trait True {}
+
+impl True for Bool<true> {}
+
+fn test<T, const P: usize>() where Bool<{core::mem::size_of::<T>() > 4}>: True {
+    todo!()
+}
+
+fn main() {
+    test::<2>();
+    //~^ ERROR wrong number of type
+    //~| ERROR constant expression depends
+}
diff --git a/src/test/ui/const-generics/issues/issue-76595.stderr b/src/test/ui/const-generics/issues/issue-76595.stderr
new file mode 100644
index 0000000000000..4235bdc9b893c
--- /dev/null
+++ b/src/test/ui/const-generics/issues/issue-76595.stderr
@@ -0,0 +1,21 @@
+error[E0107]: wrong number of type arguments: expected 1, found 0
+  --> $DIR/issue-76595.rs:15:5
+   |
+LL |     test::<2>();
+   |     ^^^^^^^^^ expected 1 type argument
+
+error: constant expression depends on a generic parameter
+  --> $DIR/issue-76595.rs:15:5
+   |
+LL | fn test<T, const P: usize>() where Bool<{core::mem::size_of::<T>() > 4}>: True {
+   |    ---- required by a bound in this
+...
+LL |     test::<2>();
+   |     ^^^^^^^^^
+   |
+   = note: this may fail depending on what value the parameter takes
+   = note: required by this bound in `test`
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0107`.