Remove unmatched suppressions

These are various places where cppcheck now understands c++-17, or we
have improve our code

Framework/Algorithms/src/CorrectTOFAxis.cpp

@@ -387,7 +387,7 @@ void CorrectTOFAxis::averageL2AndEPP(const API::SpectrumInfo &spectrumInfo, doub
   double eppSum = 0;
   size_t n = 0;
   const auto indexCount = static_cast<int64_t>(m_workspaceIndices.size());
-  // cppcheck-suppress syntaxError
+
   PRAGMA_OMP(parallel for if (m_eppTable->threadSafe())
              reduction(+: n, l2Sum, eppSum))
   for (int64_t i = 0; i < indexCount; ++i) {

Framework/Algorithms/src/CreateGroupingWorkspace.cpp

@@ -616,7 +616,7 @@ void CreateGroupingWorkspace::exec() {
       sortnames = true;
       GroupNames = "";
       int maxRecurseDepth = this->getProperty("MaxRecursionDepth");
-      // cppcheck-suppress syntaxError
+
           PRAGMA_OMP(parallel for schedule(dynamic, 1) )
           for (int num = 0; num < 300; ++num) {
             PARALLEL_START_INTERUPT_REGION

Framework/Algorithms/src/DiffractionFocussing2.cpp

@@ -371,7 +371,7 @@ void DiffractionFocussing2::execEvent() {
     int chunkSize = 200;
 
     int end = (totalHistProcess / chunkSize) + 1;
-    // cppcheck-suppress syntaxError
+
     PRAGMA_OMP(parallel for schedule(dynamic, 1) )
     for (int wiChunk = 0; wiChunk < end; wiChunk++) {
       PARALLEL_START_INTERUPT_REGION

Framework/Algorithms/src/FindPeaks.cpp

@@ -990,9 +990,6 @@ int FindPeaks::findPeakBackground(const MatrixWorkspace_sptr &input, int spectru
 
   // Local check whether FindPeakBackground gives a reasonable value
   vecpeakrange.resize(2);
-
-  /// @todo Remove this cppcheck suppression when #13950 is fixed
-  // cppcheck-suppress knownConditionTrueFalse
   if (fitresult > 0) {
     // Use FitPeakBackgroud's result
     size_t i_peakmin, i_peakmax;

Framework/Algorithms/src/FitPeaks.cpp

@@ -850,7 +850,6 @@ std::vector<std::shared_ptr<FitPeaksAlgorithm::PeakFitResult>> FitPeaks::fitPeak
   const int nThreads = FrameworkManager::Instance().getNumOMPThreads();
   size_t chunkSize = num_fit_result / nThreads;
 
-  // cppcheck-suppress syntaxError
   PRAGMA_OMP(parallel for schedule(dynamic, 1) )
   for (int ithread = 0; ithread < nThreads; ithread++) {
     PARALLEL_START_INTERUPT_REGION

Framework/Algorithms/src/GenerateEventsFilter.cpp

@@ -1071,7 +1071,7 @@ void GenerateEventsFilter::makeMultipleFiltersByValuesParallel(const map<size_t,
   }
 
   // Create event filters/splitters in parallel
-  // cppcheck-suppress syntaxError
+
     PRAGMA_OMP(parallel for schedule(dynamic, 1) )
     for (int i = 0; i < numThreads; ++i) {
       PARALLEL_START_INTERUPT_REGION

Framework/Algorithms/src/PDCalibration.cpp

@@ -533,7 +533,7 @@ void PDCalibration::exec() {
   // Scan the table containing the fit parameters for every peak, retrieve the
   // parameters for peaks that were successfully fitting, then use this info
   // to obtain difc, difa, and tzero for each pixel
-  // cppcheck-suppress syntaxError
+
    PRAGMA_OMP(parallel for schedule(dynamic, 1))
    for (int wkspIndex = 0; wkspIndex < NUMHIST; ++wkspIndex) {
      PARALLEL_START_INTERUPT_REGION

Framework/Algorithms/test/NormaliseToMonitorTest.h

@@ -452,7 +452,7 @@ public:
       const auto &yValues = outWS->histogram(i).y();
       for (size_t j = 0; j < yValues.size(); ++j) {
         if (specOutInfo.isMonitor(i))
-          // cppcheck-suppress syntaxError
+
           TS_ASSERT_DELTA(yValues[j], double(j + 1) / 15.0, 1e-12)
         else
           TS_ASSERT_DELTA(yValues[j], 2.0 / 15.0, 1e-12)

Framework/Crystal/src/SCDCalibratePanels.cpp

@@ -82,7 +82,7 @@ void SCDCalibratePanels::exec() {
     MyPanels.insert("East");
     MyPanels.insert("West");
     int maxRecurseDepth = 4;
-    // cppcheck-suppress syntaxError
+
     PRAGMA_OMP(parallel for schedule(dynamic, 1) )
     for (int num = 1; num < 64; ++num) {
       PARALLEL_START_INTERUPT_REGION

Framework/DataHandling/src/CreateChunkingFromInstrument.cpp

@@ -377,7 +377,7 @@ void CreateChunkingFromInstrument::exec() {
   // search the instrument for the bank names
   int maxRecurseDepth = this->getProperty(PARAM_MAX_RECURSE);
   map<string, vector<string>> grouping;
-  // cppcheck-suppress syntaxError
+
     PRAGMA_OMP(parallel for schedule(dynamic, 1) )
     for (int num = 0; num < maxBankNum; ++num) {
       PARALLEL_START_INTERUPT_REGION

Framework/DataHandling/src/FilterEventsByLogValuePreNexus.cpp

@@ -871,7 +871,7 @@ void FilterEventsByLogValuePreNexus::procEvents(DataObjects::EventWorkspace_sptr
   g_log.information() << "Processing input event preNexus by " << numThreads << " threads"
                       << " in " << numBlocks << " blocks. "
                       << "\n";
-  // cppcheck-suppress syntaxError
+
     PRAGMA_OMP( parallel for schedule(dynamic, 1) if (m_parallelProcessing) )
     for (int i = 0; i < int(numThreads); i++) {
       // This is the partial workspace we are about to create (if in parallel)

Framework/DataHandling/src/LoadEventPreNexus2.cpp

@@ -718,7 +718,7 @@ void LoadEventPreNexus2::procEvents(DataObjects::EventWorkspace_sptr &workspace)
   partWorkspaces.resize(numThreads);
   buffers.resize(numThreads);
   eventVectors = new EventVector_pt *[numThreads];
-  // cppcheck-suppress syntaxError
+
     PRAGMA_OMP( parallel for if (parallelProcessing) )
     for (int i = 0; i < int(numThreads); i++) {
       // This is the partial workspace we are about to create (if in parallel)

Framework/DataHandling/src/LoadRKH.cpp

@@ -518,7 +518,6 @@ const std::string LoadRKH::readUnit(const std::string &line) {
     // however to use is safely other checks would be required that would impair
     // readability, therefore in this case the unlikely performance hit is
     // accepted.
-    // cppcheck-suppress stlIfStrFind
     if (unit.find('(') != 0 || unit.find(')') != unit.size()) {
       std::string qCode = std::to_string(SaveRKH::Q_CODE);
       if (symbol == qCode && theQuantity == "q" &&

Framework/DataHandling/src/LoadRaw/isisraw.cpp

@@ -906,7 +906,6 @@ int ISISRAW::vmstime(char *timbuf, int len, time_t time_value) {
    * get time in VMS format 01-JAN-1970 00:00:00
    */
   size_t i, n;
-  // cppcheck-suppress redundantAssignment
   struct tm *tmstruct = nullptr;
 #ifdef MS_VISUAL_STUDIO
   errno_t err = localtime_s(tmstruct, &time_value);

Framework/DataHandling/src/SaveDiffCal.cpp

@@ -100,7 +100,6 @@ std::map<std::string, std::string> SaveDiffCal::validateInputs() {
  */
 void SaveDiffCal::writeDoubleFieldFromTable(H5::Group &group, const std::string &name) {
   auto column = m_calibrationWS->getColumn(name);
-  // cppcheck-suppress compareBoolExpressionWithInt
   // Retrieve only the first m_numValues, not necessarily the whole column
   auto data = column->numeric_fill<>(m_numValues);
   H5Util::writeArray1D(group, name, data);

Framework/DataHandling/src/SaveReflectometryAscii.cpp

@@ -136,7 +136,7 @@ bool SaveReflectometryAscii::includeQResolution() const {
  *  @param firstColumn :: true if the value is the first column in the output
  */
 template <typename T> void SaveReflectometryAscii::outputval(const T &val, bool firstColumn) {
-  // cppcheck-suppress syntaxError
+
   if constexpr (std::is_floating_point<T>::value) {
     if (std::isinf(val))
       return outputval("inf", firstColumn);

Framework/DataObjects/src/EventList.cpp

@@ -946,13 +946,13 @@ void EventList::setSortOrder(const EventSortType order) const { this->order = or
 /** Sort events by TOF in one thread */
 void EventList::sortTof() const {
   // nothing to do
-  if (this->order == TOF_SORT) // cppcheck-suppress identicalConditionAfterEarlyExit
+  if (this->order == TOF_SORT)
     return;
 
   // Avoid sorting from multiple threads
   std::lock_guard<std::mutex> _lock(m_sortMutex);
   // If the list was sorted while waiting for the lock, return.
-  if (this->order == TOF_SORT) // cppcheck-suppress identicalConditionAfterEarlyExit
+  if (this->order == TOF_SORT)
     return;
 
   switch (eventType) {
@@ -1012,13 +1012,13 @@ void EventList::sortTimeAtSample(const double &tofFactor, const double &tofShift
 // --------------------------------------------------------------------------
 /** Sort events by Frame */
 void EventList::sortPulseTime() const {
-  if (this->order == PULSETIME_SORT) // cppcheck-suppress identicalConditionAfterEarlyExit
-    return;                          // nothing to do
+  if (this->order == PULSETIME_SORT)
+    return; // nothing to do
 
   // Avoid sorting from multiple threads
   std::lock_guard<std::mutex> _lock(m_sortMutex);
   // If the list was sorted while waiting for the lock, return.
-  if (this->order == PULSETIME_SORT) // cppcheck-suppress identicalConditionAfterEarlyExit
+  if (this->order == PULSETIME_SORT)
     return;
 
   // Perform sort.
@@ -1042,13 +1042,13 @@ void EventList::sortPulseTime() const {
  * (the absolute time)
  */
 void EventList::sortPulseTimeTOF() const {
-  if (this->order == PULSETIMETOF_SORT) // cppcheck-suppress identicalConditionAfterEarlyExit
-    return;                             // already ordered
+  if (this->order == PULSETIMETOF_SORT)
+    return; // already ordered
 
   // Avoid sorting from multiple threads
   std::lock_guard<std::mutex> _lock(m_sortMutex);
   // If the list was sorted while waiting for the lock, return.
-  if (this->order == PULSETIMETOF_SORT) // cppcheck-suppress identicalConditionAfterEarlyExit
+  if (this->order == PULSETIMETOF_SORT)
     return;
 
   switch (eventType) {

Framework/Kernel/src/ConfigService.cpp

@@ -1237,7 +1237,6 @@ std::string ConfigServiceImpl::getDirectoryOfExecutable() const {
 std::string ConfigServiceImpl::getPathToExecutable() const {
   std::string execpath;
   const size_t LEN(1024);
-  // cppcheck-suppress variableScope
   char pBuf[LEN];
 
 #ifdef _WIN32

Framework/LiveData/src/ISIS/DAE/isisds_command.cpp

@@ -65,7 +65,6 @@ typedef struct {
   int ver_minor;
   int pid;
   int access_type; /* 0 =dae, 1 = crpt */
-                   // cppcheck-suppress unusedStructMember
   int pad[1];
   char user[32];
   char host[64];

Framework/MDAlgorithms/src/ApplyDetailedBalanceMD.cpp

@@ -190,7 +190,7 @@ void ApplyDetailedBalanceMD::applyDetailedBalance(typename Mantid::DataObjects::
 
   // Add the boxes in parallel. They should be spread out enough on each
   // core to avoid stepping on each other.
-  // cppcheck-suppress syntaxError
+
   PRAGMA_OMP( parallel for if (!ws->isFileBacked()))
   for (int i = 0; i < numBoxes; ++i) {
     PARALLEL_START_INTERUPT_REGION