From dc84daf7e8a8ae5eb5a57ed9dbbcc763d5f29cee Mon Sep 17 00:00:00 2001
From: Pietro Fezzardi <pietro@rev.ng>
Date: Wed, 3 Feb 2021 12:00:04 +0100
Subject: [PATCH] DLATypeSystem: add assertion on mergeNodes

The mergeNodes API is not guaranteed to work properly if the 2 merged
nodes are the same.
This commit adds an assertion to rule this situation out.
---
 lib/Decompiler/DLATypeSystem.cpp | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/Decompiler/DLATypeSystem.cpp b/lib/Decompiler/DLATypeSystem.cpp
index dc3f65e6a..1c12bfd9c 100644
--- a/lib/Decompiler/DLATypeSystem.cpp
+++ b/lib/Decompiler/DLATypeSystem.cpp
@@ -471,6 +471,7 @@ inline void
 LayoutTypeSystem::mergeNodes(LayoutTypeSystemNode *From,
                              LayoutTypeSystemNode *Into,
                              llvm::SmallSet<LayoutTypePtr, 2> *IntoTypePtrs) {
+  revng_assert(From != Into);
   revng_log(MergeLog, "Merging: " << From << " Into: " << Into);
   auto LayoutIt = Layouts.find(From);
   revng_assert(LayoutIt != Layouts.end());