From ec75b2fc929fecaa2371e7aee51e6a6d5ec25b27 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Th=C3=A9ophile=20Bastian?= <contact@tobast.fr>
Date: Tue, 11 Jun 2019 03:22:22 +0200
Subject: [PATCH] Fix tail call synthesis

---
 DwarfSynth/Simplest.ml | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/DwarfSynth/Simplest.ml b/DwarfSynth/Simplest.ml
index 138f8d4..82c63e8 100644
--- a/DwarfSynth/Simplest.ml
+++ b/DwarfSynth/Simplest.ml
@@ -524,7 +524,13 @@ let process_jmp jmp (cur_reg: reg_pos)
   in
 
   match (BStd.Jmp.kind jmp) with
-  | BStd.Call call -> gen_change (-8)
+  | BStd.Call call -> (
+      (* If this call never returns (tail call), do not generate an offset of
+         -8. *)
+      match BStd.Call.return call with
+      | Some _ -> gen_change (-8)
+      | None -> None
+    )
   | BStd.Ret ret -> gen_change (8)
   | _ -> None