From a8efcd91a8f7dc107355f347996fb8dd3ba7e74a Mon Sep 17 00:00:00 2001
From: Morgan Deters <mdeters@cs.nyu.edu>
Date: Fri, 21 Feb 2014 17:15:43 -0500
Subject: [PATCH] No diamond-breaking under quantifiers (resolves bug #550).

---
 src/theory/uf/theory_uf.cpp | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/theory/uf/theory_uf.cpp b/src/theory/uf/theory_uf.cpp
index 1045c5a24..2bce77451 100644
--- a/src/theory/uf/theory_uf.cpp
+++ b/src/theory/uf/theory_uf.cpp
@@ -243,6 +243,13 @@ void TheoryUF::ppStaticLearn(TNode n, NodeBuilder<>& learned) {
   while(!workList.empty()) {
     n = workList.back();
 
+    if(n.getKind() == kind::FORALL || n.getKind() == kind::EXISTS) {
+      // unsafe to go under quantifiers; we might pull bound vars out of scope!
+      processed.insert(n);
+      workList.pop_back();
+      continue;
+    }
+
     bool unprocessedChildren = false;
     for(TNode::iterator i = n.begin(), iend = n.end(); i != iend; ++i) {
       if(processed.find(*i) == processed.end()) {
-- 
2.30.2