From 9381c1b7f9323a6ca688b8d4d4a4ec5760d95bc8 Mon Sep 17 00:00:00 2001
From: azv <azv@opencascade.com>
Date: Wed, 23 Dec 2015 16:10:53 +0300
Subject: [PATCH] Fix undo of arc creation (issue #1166)

---
 .../SolveSpaceSolver/SolveSpaceSolver_Storage.cpp   | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/src/SketchSolver/SolveSpaceSolver/SolveSpaceSolver_Storage.cpp b/src/SketchSolver/SolveSpaceSolver/SolveSpaceSolver_Storage.cpp
index 23c4995e6..e5e79492b 100644
--- a/src/SketchSolver/SolveSpaceSolver/SolveSpaceSolver_Storage.cpp
+++ b/src/SketchSolver/SolveSpaceSolver/SolveSpaceSolver_Storage.cpp
@@ -1530,15 +1530,20 @@ bool SolveSpaceSolver_Storage::removeCoincidence(ConstraintWrapperPtr theConstra
   std::map<FeaturePtr, EntityWrapperPtr>::iterator aFIt = myFeatureMap.begin();
   for (; aFIt != myFeatureMap.end(); ++aFIt) {
     for (aNotCIt = aNotCoinc.begin(); aNotCIt != aNotCoinc.end(); ++aNotCIt) {
-      if (!aFIt->second->isUsed(aNotCIt->first->baseAttribute()))
+      if (!aNotCIt->second || !aFIt->second->isUsed(aNotCIt->first->baseAttribute()))
         continue;
       std::list<EntityWrapperPtr> aSubs = aFIt->second->subEntities();
       std::list<EntityWrapperPtr>::iterator aSIt = aSubs.begin();
+      bool isUpd = false;
       for (; aSIt != aSubs.end(); ++aSIt)
-        if (*aSIt == aNotCIt->first)
+        if (*aSIt == aNotCIt->first) {
           *aSIt = aNotCIt->second;
-      aFIt->second->setSubEntities(aSubs);
-      anUpdFeatures.insert(aFIt->second);
+          isUpd = true;
+        }
+      if (isUpd) {
+        aFIt->second->setSubEntities(aSubs);
+        anUpdFeatures.insert(aFIt->second);
+      }
     }
   }
   // update features
-- 
2.30.2