Normalize function type during validation

During inlining, the callee body is normalized and has types revealed,
but some of locals corresponding to the arguments might come from the
caller body which is not. As a result the caller body does not pass
validation without additional normalization.

3 files changed, 16 insertions, 8 deletions

diff --git a/compiler/rustc_mir/src/transform/validate.rs b/compiler/rustc_mir/src/transform/validate.rs
index e1e6e71acb5..2fbfe13082f 100644
--- a/compiler/rustc_mir/src/transform/validate.rs
+++ b/compiler/rustc_mir/src/transform/validate.rs
@@ -357,7 +357,9 @@ impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> {
                 }
             }
             TerminatorKind::Call { func, args, destination, cleanup, .. } => {
+                let param_env = self.param_env.with_reveal_all_normalized(self.tcx);
                 let func_ty = func.ty(&self.body.local_decls, self.tcx);
+                let func_ty = self.tcx.normalize_erasing_regions(param_env, func_ty);
                 match func_ty.kind() {
                     ty::FnPtr(..) | ty::FnDef(..) => {}
                     _ => self.fail(
diff --git a/src/test/ui/issues/issue-50865-private-impl-trait/auxiliary/lib.rs b/src/test/ui/issues/issue-50865-private-impl-trait/auxiliary/lib.rs
index fb4bf2b8b44..f3a51b415fa 100644
--- a/src/test/ui/issues/issue-50865-private-impl-trait/auxiliary/lib.rs
+++ b/src/test/ui/issues/issue-50865-private-impl-trait/auxiliary/lib.rs
@@ -1,7 +1,3 @@
-// revisions: default miropt
-//[miropt]compile-flags: -Z mir-opt-level=2
-// ~^ This flag is for #77668, it used to be ICE.
-
 #![crate_type = "lib"]
 
 pub fn bar<P>( // Error won't happen if "bar" is not generic
diff --git a/src/test/ui/mir/mir-inlining/ice-issue-77306-1.rs b/src/test/ui/mir/mir-inlining/ice-issue-77306-1.rs
index 4d083bf2321..ccb279f7fa2 100644
--- a/src/test/ui/mir/mir-inlining/ice-issue-77306-1.rs
+++ b/src/test/ui/mir/mir-inlining/ice-issue-77306-1.rs
@@ -1,17 +1,27 @@
-// run-pass
+// Regression test for various issues related to normalization & inlining.
+// * #68347, #77306, #77668 - missed normalization during inlining.
+// * #78442 - missed normalization in validator after inlining.
+//
+// build-pass
 // compile-flags:-Zmir-opt-level=2
 
-// Previously ICEd because we did not normalize during inlining,
-// see https://github.com/rust-lang/rust/pull/77306 for more discussion.
-
 pub fn write() {
     create()()
 }
 
+pub fn write_generic<T>(_t: T) {
+    hide()();
+}
+
 pub fn create() -> impl FnOnce() {
    || ()
 }
 
+pub fn hide() -> impl Fn() {
+    write
+}
+
 fn main() {
     write();
+    write_generic(());
 }