Fix warnings from clang 5.0.

Framework/API/inc/MantidAPI/AlgorithmHistory.h

@@ -27,7 +27,7 @@ namespace Detail {
 // needing to know the implementation of CompareHistory.
 template <class T> struct CompareHistory {
   bool operator()(const boost::shared_ptr<T> &lhs,
-                  const boost::shared_ptr<T> &rhs) {
+                  const boost::shared_ptr<T> &rhs) const {
     return (*lhs) < (*rhs);
   }
 };

Framework/DataObjects/test/PeakTest.h

@@ -467,7 +467,7 @@ public:
     // test with & without extended detector space
     // extended space is a sphere, so all points should fall radius*detector
     // direction away from the detector direction with extended space
-    auto testTheta = [this, &sphereInst, &radius](const double theta) {
+    auto testTheta = [this, &sphereInst](const double theta) {
       const auto expectedDir = V3D(sin(theta), 0., cos(theta));
 
       // test without extended detector space

Framework/Kernel/inc/MantidKernel/MultiFileNameParser.h

@@ -60,7 +60,7 @@ extern const std::string ANY, LIST;
  */
 class MANTID_KERNEL_DLL ReverseCaselessCompare {
 public:
-  bool operator()(const std::string &a, const std::string &b);
+  bool operator()(const std::string &a, const std::string &b) const;
 };
 
 /**

Framework/Kernel/src/MultiFileNameParser.cpp

@@ -176,7 +176,7 @@ std::string suggestWorkspaceName(const std::vector<std::string> &fileNames) {
  * overkill.
  */
 bool ReverseCaselessCompare::operator()(const std::string &a,
-                                        const std::string &b) {
+                                        const std::string &b) const {
   std::string lowerA(a);
   std::string lowerB(b);
 

Framework/LiveData/test/KafkaEventStreamDecoderTest.h

@@ -227,7 +227,7 @@ private:
     TS_ASSERT_THROWS_NOTHING(decoder.startCapture());
     {
       std::unique_lock<std::mutex> lk(m_callbackMutex);
-      this->m_callbackCondition.wait(lk, [this, &decoder, maxIterations]() {
+      this->m_callbackCondition.wait(lk, [this, maxIterations]() {
         return this->m_niterations == maxIterations;
       });
     }