fix some warnings and set -Wno-error for cling

Author: silverweed

cling/CMakeLists.txt

@@ -1 +1,5 @@
+if (NOT MSVC)
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-error")
+endif()
+
 ROOTTEST_ADD_TESTDIRS()

root/dataframe/testIMT.cxx

@@ -36,7 +36,7 @@ void getTracks(unsigned int mu, FourVectors& tracks) {
    auto nPart = R.Poisson(mu);
    tracks.clear();
    tracks.reserve(nPart);
-   for (int i = 0; i < nPart; ++i) {
+   for (size_t i = 0; i < nPart; ++i) {
       double px = R.Gaus(0,10);
       double py = R.Gaus(0,10);
       double pt = sqrt(px*px +py*py);

root/dataframe/test_misc.cxx

@@ -19,7 +19,7 @@ void getTracks(FourVectors& tracks) {
    auto nPart = R.Poisson(5);
    tracks.clear();
    tracks.reserve(nPart);
-   for (int i = 0; i < nPart; ++i) {
+   for (size_t i = 0; i < nPart; ++i) {
       double px = R.Gaus(0,10);
       double py = R.Gaus(0,10);
       double pt = sqrt(px*px +py*py);

root/dataframe/test_read_leaves.cxx

@@ -28,7 +28,7 @@ int main()
    }
 
    RDataFrame d("t", "test_read_leaves.root");
-   auto check_a_b = [](int a, int b) {
+   auto check_a_b = []([[maybe_unused]] int a, [[maybe_unused]] int b) {
       assert(a == 1);
       assert(b == 2);
       return true;

root/dataframe/test_read_leaves_nodict.cxx

@@ -26,7 +26,7 @@ int main()
    }
 
    ROOT::RDataFrame d("t", "test_read_leaves_nodict.root");
-   auto check_a_b = [](int a, int b) {
+   auto check_a_b = []([[maybe_unused]] int a, [[maybe_unused]] int b) {
       assert(a == 1);
       assert(b == 2);
       return true;

root/io/cpp11Containers/commonUtils.h

@@ -198,20 +198,22 @@ bool IsSame<>(const TH1F& a, const TH1F& b){
       if (gVerboseComparison) std::cout << "The # of bins of the histograms differ: " << nbinsa << " " << nbinsb << std::endl;
       return false;
    }
+   const auto AreBitwiseEqual = [](auto a, auto b) {
+     ULong64_t la, lb;
+     memcpy(&la, &a, sizeof(a));
+     memcpy(&lb, &b, sizeof(b));
+     return la == lb;
+   };
    for (int i=0;i<a.GetNbinsX();++i) {
       auto binca = a.GetBinContent(i);
-      auto bincallu = *(ULong64_t*)(&binca);
       auto bincb = b.GetBinContent(i);
-      auto bincbllu = *(ULong64_t*)(&bincb);
-      if (bincallu != bincbllu) {
+      if (!AreBitwiseEqual(binca, bincb)) {
          if (gVerboseComparison) std::cout << "The content of bin " << i << "  of the histograms differ: " << binca << " " << bincb << std::endl;
          return false;
       }
       auto binea = a.GetBinError(i);
-      auto bineallu = *(ULong64_t*)(&binea);
       auto bineb = b.GetBinError(i);
-      auto binebllu = *(ULong64_t*)(&bineb);
-      if (bineallu != binebllu) {
+      if (!AreBitwiseEqual(binea, bineb)) {
          if (gVerboseComparison) std::cout << "The error of bin " << i << "  of the histograms differ: " << binea << " " << bineb << std::endl;
          return false;
       }