diff --git a/polly/include/polly/ScopDetection.h b/polly/include/polly/ScopDetection.h
index 34b0844176e3..d0b588e9fdd6 100644
--- a/polly/include/polly/ScopDetection.h
+++ b/polly/include/polly/ScopDetection.h
@@ -144,7 +144,7 @@ class ScopDetection : public FunctionPass {
   RegionSet ValidRegions;
 
   // Remember a list of errors for every region.
-  mutable std::map<const Region *, RejectLog> RejectLogs;
+  mutable RejectLogsContainer RejectLogs;
 
   // Remember the invalid functions producted by backends;
   typedef std::set<const Function *> FunctionSet;
diff --git a/polly/include/polly/ScopDetectionDiagnostic.h b/polly/include/polly/ScopDetectionDiagnostic.h
index 3f6a8b3082d1..2ab7ea8f8105 100644
--- a/polly/include/polly/ScopDetectionDiagnostic.h
+++ b/polly/include/polly/ScopDetectionDiagnostic.h
@@ -173,12 +173,52 @@ public:
 
   iterator begin() const { return ErrorReports.begin(); }
   iterator end() const { return ErrorReports.end(); }
-  size_t size() { return ErrorReports.size(); }
+  size_t size() const { return ErrorReports.size(); }
 
   const Region *region() const { return R; }
   void report(RejectReasonPtr Reject) { ErrorReports.push_back(Reject); }
 };
 
+/// @brief Store reject logs
+class RejectLogsContainer {
+  std::map<const Region *, RejectLog> Logs;
+
+public:
+  typedef std::map<const Region *, RejectLog>::iterator iterator;
+  typedef std::map<const Region *, RejectLog>::const_iterator const_iterator;
+
+  iterator begin() { return Logs.begin(); }
+  iterator end() { return Logs.end(); }
+
+  const_iterator begin() const { return Logs.begin(); }
+  const_iterator end() const { return Logs.end(); }
+
+  void insert(std::pair<const Region *, RejectLog> New) {
+    auto Result = Logs.insert(New);
+    assert(Result.second && "Tried to replace an element in the log!");
+  }
+
+  std::map<const Region *, RejectLog>::mapped_type at(const Region *R) {
+    return Logs.at(R);
+  }
+
+  void clear() { Logs.clear(); }
+
+  size_t count(const Region *R) const { return Logs.count(R); }
+
+  size_t size(const Region *R) const {
+    if (!Logs.count(R))
+      return 0;
+    return Logs.at(R).size();
+  }
+
+  bool hasErrors(const Region *R) const {
+    return (Logs.count(R) && Logs.at(R).size() > 0);
+  }
+
+  bool hasErrors(Region *R) const { return hasErrors((const Region *)R); }
+};
+
 //===----------------------------------------------------------------------===//
 /// @brief Base class for CFG related reject reasons.
 ///
diff --git a/polly/lib/Analysis/ScopDetection.cpp b/polly/lib/Analysis/ScopDetection.cpp
index d63db2563a18..be147cc0c238 100644
--- a/polly/lib/Analysis/ScopDetection.cpp
+++ b/polly/lib/Analysis/ScopDetection.cpp
@@ -707,12 +707,8 @@ bool ScopDetection::isValidRegion(Region &R) const {
   bool RegionIsValid = isValidRegion(Context);
   bool HasErrors = !RegionIsValid || Context.Log.size() > 0;
 
-  if (PollyTrackFailures && HasErrors) {
-    // std::map::insert does not replace.
-    std::pair<reject_iterator, bool> InsertedValue =
-        RejectLogs.insert(std::make_pair(&R, Context.Log));
-    assert(InsertedValue.second && "Two logs generated for the same Region.");
-  }
+  if (PollyTrackFailures && HasErrors)
+    RejectLogs.insert(std::make_pair(&R, Context.Log));
 
   return RegionIsValid;
 }