From 32ee368c867d2aa977ebaca79b4b5ed8ed689fa3 Mon Sep 17 00:00:00 2001
From: Mara Bos <m-ou.se@m-ou.se>
Date: Thu, 3 Jun 2021 15:41:48 +0200
Subject: [PATCH 1/2] Show `::{{constructor}}` in std::any::type_name().

---
 compiler/rustc_mir/src/interpret/intrinsics/type_name.rs | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/compiler/rustc_mir/src/interpret/intrinsics/type_name.rs b/compiler/rustc_mir/src/interpret/intrinsics/type_name.rs
index ae5e78ee33f47..2707d138e6a2c 100644
--- a/compiler/rustc_mir/src/interpret/intrinsics/type_name.rs
+++ b/compiler/rustc_mir/src/interpret/intrinsics/type_name.rs
@@ -1,5 +1,5 @@
 use rustc_hir::def_id::CrateNum;
-use rustc_hir::definitions::{DefPathData, DisambiguatedDefPathData};
+use rustc_hir::definitions::DisambiguatedDefPathData;
 use rustc_middle::mir::interpret::Allocation;
 use rustc_middle::ty::{
     self,
@@ -127,11 +127,6 @@ impl<'tcx> Printer<'tcx> for AbsolutePathPrinter<'tcx> {
     ) -> Result<Self::Path, Self::Error> {
         self = print_prefix(self)?;
 
-        // Skip `::{{constructor}}` on tuple/unit structs.
-        if disambiguated_data.data == DefPathData::Ctor {
-            return Ok(self);
-        }
-
         write!(self.path, "::{}", disambiguated_data.data).unwrap();
 
         Ok(self)

From e3b19e5c25d2de305939a5cc73dcbdf3ae64bd94 Mon Sep 17 00:00:00 2001
From: Mara Bos <m-ou.se@m-ou.se>
Date: Thu, 3 Jun 2021 15:48:33 +0200
Subject: [PATCH 2/2] Add test for issue 84666.

---
 library/core/tests/any.rs | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/library/core/tests/any.rs b/library/core/tests/any.rs
index b0dc99034644a..b36d6f0d40405 100644
--- a/library/core/tests/any.rs
+++ b/library/core/tests/any.rs
@@ -114,3 +114,16 @@ fn any_unsized() {
     fn is_any<T: Any + ?Sized>() {}
     is_any::<[i32]>();
 }
+
+#[test]
+fn distinct_type_names() {
+    // https://github.com/rust-lang/rust/issues/84666
+
+    struct Velocity(f32, f32);
+
+    fn type_name_of_val<T>(_: T) -> &'static str {
+        type_name::<T>()
+    }
+
+    assert_ne!(type_name_of_val(Velocity), type_name_of_val(Velocity(0.0, -9.8)),);
+}