From fed4c5d9e13e7cde3399336342a64ba23308d4f5 Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Sun, 3 Feb 2019 13:31:50 +0100
Subject: [PATCH] disambiguate filenames of multiple drop shims being dumped

---
 src/librustc_mir/util/pretty.rs | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/src/librustc_mir/util/pretty.rs b/src/librustc_mir/util/pretty.rs
index 120055ad39764..48a6fd3a95df6 100644
--- a/src/librustc_mir/util/pretty.rs
+++ b/src/librustc_mir/util/pretty.rs
@@ -186,10 +186,29 @@ fn dump_path(
     let item_name = tcx
         .def_path(source.def_id())
         .to_filename_friendly_no_crate();
+    // All drop shims have the same DefId, so we have to add the type
+    // to get unique file names.
+    let shim_disambiguator = match source.instance {
+        ty::InstanceDef::DropGlue(_, Some(ty)) => {
+            // Unfortunately, pretty-printed typed are not very filename-friendly.
+            // We dome some filtering.
+            let mut s = ".".to_owned();
+            s.extend(ty.to_string()
+                .chars()
+                .filter_map(|c| match c {
+                    ' ' => None,
+                    ':' => Some('_'),
+                    c => Some(c)
+                }));
+            s
+        }
+        _ => String::new(),
+    };
 
     let file_name = format!(
-        "rustc.{}{}{}.{}.{}.{}",
+        "rustc.{}{}{}{}.{}.{}.{}",
         item_name,
+        shim_disambiguator,
         promotion_id,
         pass_num,
         pass_name,