diff --git a/bindings/CXX11/adios2/cxx11/fstream/ADIOS2fstream.tcc b/bindings/CXX11/adios2/cxx11/fstream/ADIOS2fstream.tcc
index e9e258455e..491e5e8835 100644
--- a/bindings/CXX11/adios2/cxx11/fstream/ADIOS2fstream.tcc
+++ b/bindings/CXX11/adios2/cxx11/fstream/ADIOS2fstream.tcc
@@ -15,6 +15,19 @@
 
 #include "adios2/core/Stream.h"
 
+
+#if defined(_MSC_VER)
+#pragma warning( push )
+//#pragma warning( disable : 4101)
+#elif defined(__GNUC__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wstrict-aliasing"
+
+#elif defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-wstrict-aliasing"
+#endif
+
 namespace adios2
 {
 
@@ -182,4 +195,13 @@ std::vector<T> fstream::read_attribute(const std::string &name,
 
 } // end namespace adios2
 
+
+#if defined(_MSC_VER)
+#pragma warning( pop )
+#elif defined(__GNUC__)
+#pragma GCC diagnostic pop
+#elif defined(__clang__)
+#pragma clang diagnostic pop
+#endif
+
 #endif /* ADIOS2_BINDINGS_CXX11_CXX11_FSTREAM_ADIOS2FSTREAM_TCC_ */
diff --git a/cmake/DetectOptions.cmake b/cmake/DetectOptions.cmake
index b820e42544..4981a138c1 100644
--- a/cmake/DetectOptions.cmake
+++ b/cmake/DetectOptions.cmake
@@ -150,6 +150,7 @@ if(ADIOS2_USE_Fortran STREQUAL AUTO)
   endif()
 elseif(ADIOS2_USE_Fortran)
   enable_language(Fortran)
+  string(APPEND CMAKE_Fortran_FLAGS_DEBUG " -Wall")
 endif()
 if(CMAKE_Fortran_COMPILER_LOADED)
   set(ADIOS2_HAVE_Fortran TRUE)
diff --git a/cmake/FindPythonModule.cmake b/cmake/FindPythonModule.cmake
index 4f9cf29f57..7a71efb78c 100644
--- a/cmake/FindPythonModule.cmake
+++ b/cmake/FindPythonModule.cmake
@@ -141,7 +141,7 @@ if(PythonModule_${module_NAME}_FOUND AND
   add_library(${module_NAME} INTERFACE)
   add_library(Python::${module_NAME} ALIAS ${module_NAME})
   foreach(inc_var IN LISTS include_vars)
-    target_include_directories(${module_NAME} INTERFACE ${${inc_var}})
+    target_include_directories(${module_NAME} SYSTEM INTERFACE ${${inc_var}})
   endforeach()
   foreach(lib_var IN LISTS library_vars)
     target_link_libraries(${module_NAME} INTERFACE ${${lib_var}})
diff --git a/examples/basics/values/values_write.cpp b/examples/basics/values/values_write.cpp
index 668cffa62c..5e6070664f 100644
--- a/examples/basics/values/values_write.cpp
+++ b/examples/basics/values/values_write.cpp
@@ -71,6 +71,7 @@ int main(int argc, char *argv[])
          */
         // 1. Global constant, same value across processes, constant over time
         adios2::Variable<int> varNproc = io.DefineVariable<int>("Nproc");
+        (void)varNproc; // For the sake of the example we create an unused variable
 
         // 2. Global value, same value across processes, varying value over time
         adios2::Variable<int> varStep = io.DefineVariable<int>("Step");
diff --git a/examples/hello/bpReader/helloBPReader_nompi.cpp b/examples/hello/bpReader/helloBPReader_nompi.cpp
index 776543d8a5..7e5038c6c9 100644
--- a/examples/hello/bpReader/helloBPReader_nompi.cpp
+++ b/examples/hello/bpReader/helloBPReader_nompi.cpp
@@ -36,7 +36,7 @@ int main(int argc, char *argv[])
             bpIO.AvailableVariables(true);
 
         std::cout << "List of variables:";
-        for (const auto variablePair : variables)
+        for (const auto& variablePair : variables)
         {
             std::cout << "  " << variablePair.first;
         }
diff --git a/examples/hello/bpWriter/helloBPSubStreams.cpp b/examples/hello/bpWriter/helloBPSubStreams.cpp
index 73e9412775..2a2fabcf2a 100644
--- a/examples/hello/bpWriter/helloBPSubStreams.cpp
+++ b/examples/hello/bpWriter/helloBPSubStreams.cpp
@@ -67,6 +67,7 @@ int main(int argc, char *argv[])
 
         adios2::Attribute<int> attribute =
             bpIO.DefineAttribute<int>("attrINT", -1);
+        (void)attribute; // For the sake of the example we create an unused variable
 
         /** Engine derived class, spawned to start IO operations */
         adios2::Engine bpFileWriter =
diff --git a/examples/hello/bpWriter/helloBPWriter.cpp b/examples/hello/bpWriter/helloBPWriter.cpp
index e67c82ba92..4d93a35f72 100644
--- a/examples/hello/bpWriter/helloBPWriter.cpp
+++ b/examples/hello/bpWriter/helloBPWriter.cpp
@@ -63,6 +63,7 @@ int main(int argc, char *argv[])
 
         adios2::Variable<std::string> bpString =
             bpIO.DefineVariable<std::string>("bpString");
+        (void)bpString; // For the sake of the example we create an unused variable
 
         std::string filename = "myVector_cpp.bp";
         /** Engine derived class, spawned to start IO operations */
diff --git a/examples/hello/hdf5Reader/helloHDF5Reader_nompi.cpp b/examples/hello/hdf5Reader/helloHDF5Reader_nompi.cpp
index a6f64151ad..22e2dd9922 100644
--- a/examples/hello/hdf5Reader/helloHDF5Reader_nompi.cpp
+++ b/examples/hello/hdf5Reader/helloHDF5Reader_nompi.cpp
@@ -93,7 +93,7 @@ int main(int argc, char *argv[])
         const std::map<std::string, adios2::Params> variables =
             h5IO.AvailableVariables();
 
-        for (const auto variablePair : variables)
+        for (const auto& variablePair : variables)
         {
             std::cout << "Name: " << variablePair.first;
             std::cout << std::endl;
diff --git a/scripts/ci/cmake/ci-el7-gnu8-ohpc.cmake b/scripts/ci/cmake/ci-el7-gnu8-ohpc.cmake
index 6bbc905f82..a315186076 100644
--- a/scripts/ci/cmake/ci-el7-gnu8-ohpc.cmake
+++ b/scripts/ci/cmake/ci-el7-gnu8-ohpc.cmake
@@ -10,9 +10,9 @@ env_module(load hdf5)
 set(ENV{CC}  gcc)
 set(ENV{CXX} g++)
 set(ENV{FC}  gfortran)
-set(ENV{CFLAGS} "-Werror -Wno-error=builtin-declaration-mismatch")
-set(ENV{CXXFLAGS} "-Werror -Wno-error=builtin-declaration-mismatch")
-set(ENV{FFLAGS} "-Werror -Wno-error=builtin-declaration-mismatch")
+set(ENV{CFLAGS}   "-Werror -Wall -Wno-error=builtin-declaration-mismatch")
+set(ENV{CXXFLAGS} "-Werror -Wall -Wno-error=builtin-declaration-mismatch")
+set(ENV{FFLAGS}   "-Werror -Wall -Wno-error=builtin-declaration-mismatch")
 
 set(dashboard_cache "
 ADIOS2_USE_BZip2:BOOL=ON
diff --git a/scripts/ci/cmake/ci-el7-gnu8-openmpi-ohpc-static.cmake b/scripts/ci/cmake/ci-el7-gnu8-openmpi-ohpc-static.cmake
index 581be161aa..2d2fabdbe7 100644
--- a/scripts/ci/cmake/ci-el7-gnu8-openmpi-ohpc-static.cmake
+++ b/scripts/ci/cmake/ci-el7-gnu8-openmpi-ohpc-static.cmake
@@ -16,9 +16,9 @@ env_module(load py3-mpi4py)
 set(ENV{CC}  gcc)
 set(ENV{CXX} g++)
 set(ENV{FC}  gfortran)
-set(ENV{CFLAGS} "-Werror -Wno-error=builtin-declaration-mismatch")
-set(ENV{CXXFLAGS} "-Werror -Wno-error=builtin-declaration-mismatch")
-set(ENV{FFLAGS} "-Werror -Wno-error=builtin-declaration-mismatch")
+set(ENV{CFLAGS}   "-Werror -Wall -Wno-error=builtin-declaration-mismatch")
+set(ENV{CXXFLAGS} "-Werror -Wall -Wno-error=builtin-declaration-mismatch")
+set(ENV{FFLAGS}   "-Werror -Wall -Wno-error=builtin-declaration-mismatch")
 
 set(dashboard_cache "
 BUILD_SHARED_LIBS:BOOL=OFF
diff --git a/scripts/ci/cmake/ci-el7-gnu8-openmpi-ohpc.cmake b/scripts/ci/cmake/ci-el7-gnu8-openmpi-ohpc.cmake
index 16f5ccf725..934d53119e 100644
--- a/scripts/ci/cmake/ci-el7-gnu8-openmpi-ohpc.cmake
+++ b/scripts/ci/cmake/ci-el7-gnu8-openmpi-ohpc.cmake
@@ -16,9 +16,9 @@ env_module(load py3-mpi4py)
 set(ENV{CC}  gcc)
 set(ENV{CXX} g++)
 set(ENV{FC}  gfortran)
-set(ENV{CFLAGS} "-Werror -Wno-error=builtin-declaration-mismatch")
-set(ENV{CXXFLAGS} "-Werror -Wno-error=builtin-declaration-mismatch")
-set(ENV{FFLAGS} "-Werror -Wno-error=builtin-declaration-mismatch")
+set(ENV{CFLAGS}   "-Werror -Wall -Wno-error=builtin-declaration-mismatch")
+set(ENV{CXXFLAGS} "-Werror -Wall -Wno-error=builtin-declaration-mismatch")
+set(ENV{FFLAGS}   "-Werror -Wall -Wno-error=builtin-declaration-mismatch")
 
 set(dashboard_cache "
 ADIOS2_USE_BZip2:BOOL=ON
diff --git a/scripts/ci/cmake/ci-el7-intel-ohpc.cmake b/scripts/ci/cmake/ci-el7-intel-ohpc.cmake
index 6aec07e815..4f3fec2b17 100644
--- a/scripts/ci/cmake/ci-el7-intel-ohpc.cmake
+++ b/scripts/ci/cmake/ci-el7-intel-ohpc.cmake
@@ -10,9 +10,9 @@ env_module(load hdf5)
 set(ENV{CC}  icc)
 set(ENV{CXX} icpc)
 set(ENV{FC}  ifort)
-set(ENV{CFLAGS} -Werror)
-set(ENV{CXXFLAGS} -Werror)
-set(ENV{FFLAGS} "-warn errors")
+set(ENV{CFLAGS}   "-Werror -Wall")
+set(ENV{CXXFLAGS} "-Werror -Wall")
+set(ENV{FFLAGS}   "-warn errors")
 
 set(dashboard_cache "
 ADIOS2_USE_BZip2:BOOL=ON
diff --git a/scripts/ci/cmake/ci-el7-intel-openmpi-ohpc.cmake b/scripts/ci/cmake/ci-el7-intel-openmpi-ohpc.cmake
index 696ca55aad..65377d9142 100644
--- a/scripts/ci/cmake/ci-el7-intel-openmpi-ohpc.cmake
+++ b/scripts/ci/cmake/ci-el7-intel-openmpi-ohpc.cmake
@@ -16,9 +16,9 @@ env_module(load py3-mpi4py)
 set(ENV{CC}  icc)
 set(ENV{CXX} icpc)
 set(ENV{FC}  ifort)
-set(ENV{CFLAGS} -Werror)
-set(ENV{CXXFLAGS} -Werror)
-set(ENV{FFLAGS} "-warn errors")
+set(ENV{CFLAGS}   "-Werror -Wall -Wall")
+set(ENV{CXXFLAGS} "-Werror -Wall -Wall")
+set(ENV{FFLAGS}   "-warn errors")
 
 set(dashboard_cache "
 ADIOS2_USE_BZip2:BOOL=ON
diff --git a/scripts/ci/cmake/ci-el7-spack.cmake b/scripts/ci/cmake/ci-el7-spack.cmake
index 6fcd590243..28c666ff5b 100644
--- a/scripts/ci/cmake/ci-el7-spack.cmake
+++ b/scripts/ci/cmake/ci-el7-spack.cmake
@@ -7,6 +7,9 @@ math(EXPR N2CPUS "${NCPUS}*2")
 set(ENV{CC}  gcc)
 set(ENV{CXX} g++)
 set(ENV{FC}  gfortran)
+set(ENV{CFLAGS}   "-Werror -Wall")
+set(ENV{CXXFLAGS} "-Werror -Wall")
+set(ENV{FFLAGS}   "-Werror -Wall")
 
 set(dashboard_cache "
 ADIOS2_USE_BZip2:BOOL=ON
diff --git a/scripts/ci/cmake/ci-el7.cmake b/scripts/ci/cmake/ci-el7.cmake
index 4ee0370760..21d6190cf2 100644
--- a/scripts/ci/cmake/ci-el7.cmake
+++ b/scripts/ci/cmake/ci-el7.cmake
@@ -3,9 +3,9 @@
 set(ENV{CC}  gcc)
 set(ENV{CXX} g++)
 set(ENV{FC}  gfortran)
-set(ENV{CFLAGS} -Werror)
-set(ENV{CXXFLAGS} -Werror)
-set(ENV{FFLAGS} -Werror)
+set(ENV{CFLAGS}   "-Werror -Wall")
+set(ENV{CXXFLAGS} "-Werror -Wall")
+set(ENV{FFLAGS}   "-Werror -Wall")
 
 set(dashboard_cache "
 ADIOS2_USE_BZip2:STRING=ON
diff --git a/scripts/ci/cmake/ci-macos1014-xcode103-ninja.cmake b/scripts/ci/cmake/ci-macos1014-xcode103-ninja.cmake
index b9f1eba04e..7e6857ba4c 100644
--- a/scripts/ci/cmake/ci-macos1014-xcode103-ninja.cmake
+++ b/scripts/ci/cmake/ci-macos1014-xcode103-ninja.cmake
@@ -2,6 +2,9 @@
 set(ENV{CC}  clang)
 set(ENV{CXX} clang++)
 set(ENV{FC}  gfortran)
+set(ENV{CFLAGS}   "-Werror -Wall")
+set(ENV{CXXFLAGS} "-Werror -Wall")
+set(ENV{FFLAGS}   "-Werror -Wall")
 
 set(dashboard_cache "
 ADIOS2_USE_Fortran:BOOL=ON
diff --git a/scripts/ci/cmake/ci-macos1014-xcode103-openmpi-make.cmake b/scripts/ci/cmake/ci-macos1014-xcode103-openmpi-make.cmake
index 51ba0bfc31..113ae25b1e 100644
--- a/scripts/ci/cmake/ci-macos1014-xcode103-openmpi-make.cmake
+++ b/scripts/ci/cmake/ci-macos1014-xcode103-openmpi-make.cmake
@@ -2,6 +2,9 @@
 set(ENV{CC}  clang)
 set(ENV{CXX} clang++)
 set(ENV{FC}  gfortran)
+set(ENV{CFLAGS}   "-Werror -Wall")
+set(ENV{CXXFLAGS} "-Werror -Wall")
+set(ENV{FFLAGS}   "-Werror -Wall")
 
 include(ProcessorCount)
 ProcessorCount(NCPUS)
diff --git a/scripts/ci/cmake/ci-macos1015-xcode111-make.cmake b/scripts/ci/cmake/ci-macos1015-xcode111-make.cmake
index c422af45a0..754ae327e3 100644
--- a/scripts/ci/cmake/ci-macos1015-xcode111-make.cmake
+++ b/scripts/ci/cmake/ci-macos1015-xcode111-make.cmake
@@ -2,6 +2,9 @@
 set(ENV{CC}  clang)
 set(ENV{CXX} clang++)
 set(ENV{FC}  gfortran)
+set(ENV{CFLAGS}   "-Werror -Wall")
+set(ENV{CXXFLAGS} "-Werror -Wall")
+set(ENV{FFLAGS}   "-Werror -Wall")
 
 set(dashboard_cache "
 ADIOS2_USE_Fortran:BOOL=ON
diff --git a/scripts/ci/cmake/ci-macos1015-xcode111-openmpi-ninja.cmake b/scripts/ci/cmake/ci-macos1015-xcode111-openmpi-ninja.cmake
index af2ffa94c8..f24ab25277 100644
--- a/scripts/ci/cmake/ci-macos1015-xcode111-openmpi-ninja.cmake
+++ b/scripts/ci/cmake/ci-macos1015-xcode111-openmpi-ninja.cmake
@@ -2,6 +2,9 @@
 set(ENV{CC}  clang)
 set(ENV{CXX} clang++)
 set(ENV{FC}  gfortran)
+set(ENV{CFLAGS}   "-Werror -Wall")
+set(ENV{CXXFLAGS} "-Werror -Wall")
+set(ENV{FFLAGS}   "-Werror -Wall")
 
 include(ProcessorCount)
 ProcessorCount(NCPUS)
diff --git a/scripts/ci/cmake/ci-ubuntu1804-spack.cmake b/scripts/ci/cmake/ci-ubuntu1804-spack.cmake
index 2b833980d4..a559b4bad2 100644
--- a/scripts/ci/cmake/ci-ubuntu1804-spack.cmake
+++ b/scripts/ci/cmake/ci-ubuntu1804-spack.cmake
@@ -7,9 +7,9 @@ math(EXPR N2CPUS "${NCPUS}*2")
 set(ENV{CC}  gcc)
 set(ENV{CXX} g++)
 set(ENV{FC}  gfortran)
-set(ENV{CFLAGS} "-Werror -Wno-error=builtin-declaration-mismatch")
-set(ENV{CXXFLAGS} "-Werror -Wno-error=builtin-declaration-mismatch")
-set(ENV{FFLAGS} "-Werror -Wno-error=builtin-declaration-mismatch")
+set(ENV{CFLAGS}   "-Werror -Wall -Wno-error=builtin-declaration-mismatch")
+set(ENV{CXXFLAGS} "-Werror -Wall -Wno-error=builtin-declaration-mismatch")
+set(ENV{FFLAGS}   "-Werror -Wall -Wno-error=builtin-declaration-mismatch")
 
 set(dashboard_cache "
 ADIOS2_USE_BZip2:BOOL=ON
diff --git a/source/adios2/engine/dataman/DataManMonitor.h b/source/adios2/engine/dataman/DataManMonitor.h
index e8d732e8a6..9a95cf496d 100644
--- a/source/adios2/engine/dataman/DataManMonitor.h
+++ b/source/adios2/engine/dataman/DataManMonitor.h
@@ -76,7 +76,6 @@ class DataManMonitor
     bool m_WriterThreading = false;
 
     bool m_Verbose = true;
-    bool m_JsonOutput = true;
 };
 
 } // end namespace engine
diff --git a/source/adios2/engine/sst/SstReader.cpp b/source/adios2/engine/sst/SstReader.cpp
index cb858b2f84..03158153e7 100644
--- a/source/adios2/engine/sst/SstReader.cpp
+++ b/source/adios2/engine/sst/SstReader.cpp
@@ -486,7 +486,7 @@ void SstReader::Init()
             size_t *Start = NULL;                                              \
             size_t *Count = NULL;                                              \
             size_t DimCount = 0;                                               \
-            int NeedSync;                                                      \
+            int NeedSync = 0;                                                  \
                                                                                \
             if (variable.m_SelectionType ==                                    \
                 adios2::SelectionType::BoundingBox)                            \
diff --git a/source/adios2/helper/adiosMemory.inl b/source/adios2/helper/adiosMemory.inl
index 95a2889be1..41217f5af0 100644
--- a/source/adios2/helper/adiosMemory.inl
+++ b/source/adios2/helper/adiosMemory.inl
@@ -623,7 +623,7 @@ void Resize(std::vector<T> &vec, const size_t dataSize, const std::string hint,
 // functions) and copies to the output buffer in blocks. the memory address
 // calculation complexity for copying each block is minimized to O(1), which is
 // independent of the number of dimensions.
-static void NdCopyRecurDFSeqPadding(size_t curDim, const char *&inOvlpBase,
+static inline void NdCopyRecurDFSeqPadding(size_t curDim, const char *&inOvlpBase,
                                     char *&outOvlpBase, Dims &inOvlpGapSize,
                                     Dims &outOvlpGapSize, Dims &ovlpCount,
                                     size_t &minContDim, size_t &blockSize)
@@ -666,7 +666,7 @@ static void NdCopyRecurDFSeqPadding(size_t curDim, const char *&inOvlpBase,
 // each element is minimized to average O(1), which is independent of
 // the number of dimensions.
 
-static void
+static inline void
 NdCopyRecurDFSeqPaddingRevEndian(size_t curDim, const char *&inOvlpBase,
                                  char *&outOvlpBase, Dims &inOvlpGapSize,
                                  Dims &outOvlpGapSize, Dims &ovlpCount,
@@ -707,7 +707,7 @@ NdCopyRecurDFSeqPaddingRevEndian(size_t curDim, const char *&inOvlpBase,
 // used for buffer of Column major
 // the memory address calculation complexity for copying each element is
 // minimized to average O(1), which is independent of the number of dimensions.
-static void NdCopyRecurDFNonSeqDynamic(size_t curDim, const char *inBase,
+static inline void NdCopyRecurDFNonSeqDynamic(size_t curDim, const char *inBase,
                                        char *outBase, Dims &inRltvOvlpSPos,
                                        Dims &outRltvOvlpSPos, Dims &inStride,
                                        Dims &outStride, Dims &ovlpCount,
@@ -737,7 +737,7 @@ static void NdCopyRecurDFNonSeqDynamic(size_t curDim, const char *inBase,
 // The memory address calculation complexity for copying each element is
 // minimized to average O(1), which is independent of the number of dimensions.
 
-static void NdCopyRecurDFNonSeqDynamicRevEndian(
+static inline void NdCopyRecurDFNonSeqDynamicRevEndian(
     size_t curDim, const char *inBase, char *outBase, Dims &inRltvOvlpSPos,
     Dims &outRltvOvlpSPos, Dims &inStride, Dims &outStride, Dims &ovlpCount,
     size_t elmSize)
@@ -763,7 +763,7 @@ static void NdCopyRecurDFNonSeqDynamicRevEndian(
     }
 }
 
-static void NdCopyIterDFSeqPadding(const char *&inOvlpBase, char *&outOvlpBase,
+static inline void NdCopyIterDFSeqPadding(const char *&inOvlpBase, char *&outOvlpBase,
                                    Dims &inOvlpGapSize, Dims &outOvlpGapSize,
                                    Dims &ovlpCount, size_t minContDim,
                                    size_t blockSize)
@@ -794,7 +794,7 @@ static void NdCopyIterDFSeqPadding(const char *&inOvlpBase, char *&outOvlpBase,
     }
 }
 
-static void NdCopyIterDFSeqPaddingRevEndian(
+static inline void NdCopyIterDFSeqPaddingRevEndian(
     const char *&inOvlpBase, char *&outOvlpBase, Dims &inOvlpGapSize,
     Dims &outOvlpGapSize, Dims &ovlpCount, size_t minContDim, size_t blockSize,
     size_t elmSize, size_t numElmsPerBlock)
@@ -830,7 +830,7 @@ static void NdCopyIterDFSeqPaddingRevEndian(
         } while (pos[curDim] == ovlpCount[curDim]);
     }
 }
-static void NdCopyIterDFDynamic(const char *inBase, char *outBase,
+static inline void NdCopyIterDFDynamic(const char *inBase, char *outBase,
                                 Dims &inRltvOvlpSPos, Dims &outRltvOvlpSPos,
                                 Dims &inStride, Dims &outStride,
                                 Dims &ovlpCount, size_t elmSize)
@@ -867,7 +867,7 @@ static void NdCopyIterDFDynamic(const char *inBase, char *outBase,
     }
 }
 
-static void NdCopyIterDFDynamicRevEndian(const char *inBase, char *outBase,
+static inline void NdCopyIterDFDynamicRevEndian(const char *inBase, char *outBase,
                                          Dims &inRltvOvlpSPos,
                                          Dims &outRltvOvlpSPos, Dims &inStride,
                                          Dims &outStride, Dims &ovlpCount,
diff --git a/source/adios2/helper/adiosType.inl b/source/adios2/helper/adiosType.inl
index 23eb7d02f8..a5ea08612e 100644
--- a/source/adios2/helper/adiosType.inl
+++ b/source/adios2/helper/adiosType.inl
@@ -179,7 +179,7 @@ inline std::string VectorToCSV(const std::vector<std::string> &input) noexcept
     }
 
     std::ostringstream valueSS;
-    for (const auto value : input)
+    for (const auto& value : input)
     {
         valueSS << "\"" << value << "\", ";
     }
@@ -200,7 +200,7 @@ inline std::string VectorToCSV(const std::vector<std::string> &input) noexcept
         }                                                                      \
                                                                                \
         std::ostringstream valueSS;                                            \
-        for (const auto value : input)                                         \
+        for (const auto& value : input)                                         \
         {                                                                      \
             const int valueInt = static_cast<int>(value);                      \
             valueSS << valueInt << ", ";                                       \
@@ -223,7 +223,7 @@ inline std::string VectorToCSV(const std::vector<T> &input) noexcept
     }
 
     std::ostringstream valueSS;
-    for (const auto value : input)
+    for (const auto& value : input)
     {
         valueSS << value << ", ";
     }
diff --git a/source/adios2/toolkit/format/bp/BPBase.cpp b/source/adios2/toolkit/format/bp/BPBase.cpp
index 0ec23a9a02..e41011c7e0 100644
--- a/source/adios2/toolkit/format/bp/BPBase.cpp
+++ b/source/adios2/toolkit/format/bp/BPBase.cpp
@@ -393,7 +393,7 @@ BPBase::GetTransportIDs(const std::vector<std::string> &transportsTypes) const
     std::vector<uint8_t> transportsIDs;
     transportsIDs.reserve(transportsTypes.size());
 
-    for (const std::string transportType : transportsTypes)
+    for (const std::string& transportType : transportsTypes)
     {
         transportsIDs.push_back(lf_GetTransportID(transportType));
     }
diff --git a/source/adios2/toolkit/format/dataman/DataManSerializer.tcc b/source/adios2/toolkit/format/dataman/DataManSerializer.tcc
index 1a3e3217aa..3fb88ff2a8 100644
--- a/source/adios2/toolkit/format/dataman/DataManSerializer.tcc
+++ b/source/adios2/toolkit/format/dataman/DataManSerializer.tcc
@@ -458,7 +458,7 @@ int DataManSerializer::GetData(T *outputData, const std::string &varName,
             }
             if (j.shape.empty() or (j.shape.size() == 1 and j.shape[0] == 1))
             {
-                std::memcpy(outputData, input_data, sizeof(T));
+                std::memcpy(reinterpret_cast<char *>(outputData), input_data, sizeof(T));
             }
         }
     }
diff --git a/source/adios2/toolkit/profiling/taustubs/tautimer.cpp b/source/adios2/toolkit/profiling/taustubs/tautimer.cpp
index fb0d669edb..c076b546ca 100644
--- a/source/adios2/toolkit/profiling/taustubs/tautimer.cpp
+++ b/source/adios2/toolkit/profiling/taustubs/tautimer.cpp
@@ -93,7 +93,7 @@ void (*my_Tau_destructor_trigger)(void) = NULL;
 static void initialize_library(void)
 {
     // initialize the library when it is loaded
-    static taustubs::TauTimer &tt = taustubs::TauTimer::get();
+    taustubs::TauTimer::get();
 }
 
 void open_preload_libraries(void)
diff --git a/source/adios2/toolkit/sst/dp/rdma_dp.c b/source/adios2/toolkit/sst/dp/rdma_dp.c
index 9459a443ed..fda75b5cf1 100644
--- a/source/adios2/toolkit/sst/dp/rdma_dp.c
+++ b/source/adios2/toolkit/sst/dp/rdma_dp.c
@@ -1140,7 +1140,7 @@ static void *RdmaReadRemoteMemory(CP_Services Svcs, DP_RS_Stream Stream_v,
                                   size_t Length, void *Buffer,
                                   void *DP_TimestepInfo)
 {
-    RdmaCompletionHandle ret;
+    RdmaCompletionHandle ret = {0};
     Rdma_RS_Stream RS_Stream = (Rdma_RS_Stream)Stream_v;
     RdmaBufferHandle Info = (RdmaBufferHandle)DP_TimestepInfo;
     RdmaStepLogEntry StepLog;
@@ -1540,9 +1540,10 @@ static void RdmaDestroyReader(CP_Services Svcs, DP_RS_Stream RS_Stream_v)
 static void RdmaDestroyWriterPerReader(CP_Services Svcs,
                                        DP_WSR_Stream WSR_Stream_v)
 {
-    Rdma_WSR_Stream WSR_Stream = (Rdma_WSR_Stream)WSR_Stream_v;
+    Rdma_WSR_Stream WSR_Stream = {0};
+    memcpy(&WSR_Stream, &WSR_Stream_v, sizeof(Rdma_WSR_Stream));
     Rdma_WS_Stream WS_Stream = WSR_Stream->WS_Stream;
-    RdmaWriterContactInfo WriterContactInfo;
+    RdmaWriterContactInfo WriterContactInfo = {0};
 
     pthread_mutex_lock(&wsr_mutex);
     for (int i = 0; i < WS_Stream->ReaderCount; i++)
diff --git a/source/adios2/toolkit/zmq/zmqreqrep/ZmqReqRep.h b/source/adios2/toolkit/zmq/zmqreqrep/ZmqReqRep.h
index 6afa8d266f..56cae2b2aa 100644
--- a/source/adios2/toolkit/zmq/zmqreqrep/ZmqReqRep.h
+++ b/source/adios2/toolkit/zmq/zmqreqrep/ZmqReqRep.h
@@ -45,7 +45,6 @@ class ZmqReqRep
     void SendReply(const void *reply, const size_t size);
 
 private:
-    int m_Verbosity = 0;
     int m_Timeout;
 
     std::vector<char> m_ReceiverBuffer;
diff --git a/source/h5vol/H5VolError.h b/source/h5vol/H5VolError.h
index 1437bac82a..a924c6a58f 100644
--- a/source/h5vol/H5VolError.h
+++ b/source/h5vol/H5VolError.h
@@ -10,8 +10,8 @@ void *safe_calloc(size_t n, size_t s, unsigned long line);
 void *safe_malloc(size_t n, unsigned long line);
 #define SAFE_MALLOC(n) safe_malloc(n, __LINE__)
 
-void safe_free(void *p);
-#define SAFE_FREE(ptr) safe_free(ptr)
+void safe_free(void **p);
+#define SAFE_FREE(ptr) safe_free(&ptr)
 
 void *safe_ralloc(void *ptr, size_t newsize, unsigned long line);
 #define SAFE_REALLOC(ptr, newsize) safe_ralloc(ptr, newsize, __LINE__)
diff --git a/source/h5vol/H5VolUtil.c b/source/h5vol/H5VolUtil.c
index 6f44a18c70..b58d0d6c1a 100644
--- a/source/h5vol/H5VolUtil.c
+++ b/source/h5vol/H5VolUtil.c
@@ -35,7 +35,7 @@ void *safe_malloc(size_t n, unsigned long line)
     return p;
 }
 
-void safe_free(void *p)
+void safe_free(void **p)
 {
     if (p)
     {
diff --git a/testing/adios2/engine/bp/TestBPWriteAppendReadADIOS2.cpp b/testing/adios2/engine/bp/TestBPWriteAppendReadADIOS2.cpp
index ef7288f05a..4d16ddf9e6 100644
--- a/testing/adios2/engine/bp/TestBPWriteAppendReadADIOS2.cpp
+++ b/testing/adios2/engine/bp/TestBPWriteAppendReadADIOS2.cpp
@@ -15,6 +15,20 @@
 
 #include "../SmallTestData.h"
 
+#if defined(_MSC_VER)
+#pragma warning( push )
+//#pragma warning( disable : 4101)
+#elif defined(__GNUC__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wstrict-aliasing"
+#pragma GCC diagnostic ignored "-Wunused-variable"
+
+#elif defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wstrict-aliasing"
+#pragma clang diagnostic ignored "-Wunused-variable"
+#endif
+
 std::string engineName; // comes from command line
 
 class BPWriteAppendReadTestADIOS2 : public ::testing::Test
@@ -733,3 +747,12 @@ int main(int argc, char **argv)
 
     return result;
 }
+
+#if defined(_MSC_VER)
+#pragma warning( pop )
+#elif defined(__GNUC__)
+#pragma GCC diagnostic pop
+#elif defined(__clang__)
+#pragma clang diagnostic pop
+#endif
+
diff --git a/testing/adios2/engine/bp/TestBPWriteReadAsStreamADIOS2.cpp b/testing/adios2/engine/bp/TestBPWriteReadAsStreamADIOS2.cpp
index a0b868afcf..4ee9aef524 100644
--- a/testing/adios2/engine/bp/TestBPWriteReadAsStreamADIOS2.cpp
+++ b/testing/adios2/engine/bp/TestBPWriteReadAsStreamADIOS2.cpp
@@ -14,6 +14,18 @@
 
 #include "../SmallTestData.h"
 
+#if defined(_MSC_VER)
+#pragma warning( push )
+//#pragma warning( disable : 4101)
+#elif defined(__GNUC__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wunused-variable"
+
+#elif defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-variable"
+#endif
+
 std::string engineName; // comes from command line
 
 class BPWriteReadAsStreamTestADIOS2 : public ::testing::Test
@@ -1070,3 +1082,12 @@ int main(int argc, char **argv)
 
     return result;
 }
+
+#if defined(_MSC_VER)
+#pragma warning( pop )
+#elif defined(__GNUC__)
+#pragma GCC diagnostic pop
+#elif defined(__clang__)
+#pragma clang diagnostic pop
+#endif
+
diff --git a/testing/adios2/engine/bp/TestBPWriteReadAttributesMultirank.cpp b/testing/adios2/engine/bp/TestBPWriteReadAttributesMultirank.cpp
index baddebc521..c68f58dbaf 100644
--- a/testing/adios2/engine/bp/TestBPWriteReadAttributesMultirank.cpp
+++ b/testing/adios2/engine/bp/TestBPWriteReadAttributesMultirank.cpp
@@ -17,6 +17,19 @@
 
 #include <gtest/gtest.h>
 
+#if defined(_MSC_VER)
+#pragma warning( push )
+//#pragma warning( disable : 4101)
+#elif defined(__GNUC__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wunused-variable"
+
+#elif defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-variable"
+#endif
+
+
 std::string engineName; // comes from command line
 
 class BPWriteReadAttributeTestMultirank : public ::testing::Test
@@ -137,3 +150,12 @@ int main(int argc, char **argv)
 
     return result;
 }
+
+#if defined(_MSC_VER)
+#pragma warning( pop )
+#elif defined(__GNUC__)
+#pragma GCC diagnostic pop
+#elif defined(__clang__)
+#pragma clang diagnostic pop
+#endif
+
diff --git a/testing/adios2/engine/bp/TestBPWriteReadLocalVariables.cpp b/testing/adios2/engine/bp/TestBPWriteReadLocalVariables.cpp
index 1feaeb246e..b18e47e4ea 100644
--- a/testing/adios2/engine/bp/TestBPWriteReadLocalVariables.cpp
+++ b/testing/adios2/engine/bp/TestBPWriteReadLocalVariables.cpp
@@ -15,6 +15,18 @@
 
 #include "../SmallTestData.h"
 
+#if defined(_MSC_VER)
+#pragma warning( push )
+//#pragma warning( disable : 4101)
+#elif defined(__GNUC__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wunused-variable"
+
+#elif defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-variable"
+#endif
+
 std::string engineName; // comes from command line
 
 class BPWriteReadLocalVariables : public ::testing::Test
@@ -1948,3 +1960,13 @@ int main(int argc, char **argv)
 
     return result;
 }
+
+
+#if defined(_MSC_VER)
+#pragma warning( pop )
+#elif defined(__GNUC__)
+#pragma GCC diagnostic pop
+#elif defined(__clang__)
+#pragma clang diagnostic pop
+#endif
+
diff --git a/testing/adios2/engine/bp/TestBPWriteReadVariableSpan.cpp b/testing/adios2/engine/bp/TestBPWriteReadVariableSpan.cpp
index f59d273186..d2c6b2c063 100644
--- a/testing/adios2/engine/bp/TestBPWriteReadVariableSpan.cpp
+++ b/testing/adios2/engine/bp/TestBPWriteReadVariableSpan.cpp
@@ -14,6 +14,18 @@
 
 #include "../SmallTestData.h"
 
+#if defined(_MSC_VER)
+#pragma warning( push )
+//#pragma warning( disable : 4101)
+#elif defined(__GNUC__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wunused-variable"
+
+#elif defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-variable"
+#endif
+
 std::string engineName; // comes from command line
 
 class BPWriteReadSpan : public ::testing::Test
@@ -1535,3 +1547,12 @@ int main(int argc, char **argv)
 
     return result;
 }
+
+#if defined(_MSC_VER)
+#pragma warning( pop )
+#elif defined(__GNUC__)
+#pragma GCC diagnostic pop
+#elif defined(__clang__)
+#pragma clang diagnostic pop
+#endif
+
diff --git a/testing/adios2/engine/bp/operations/TestBPWriteReadZfpConfig.cpp b/testing/adios2/engine/bp/operations/TestBPWriteReadZfpConfig.cpp
index 5adcc94a25..303481a180 100644
--- a/testing/adios2/engine/bp/operations/TestBPWriteReadZfpConfig.cpp
+++ b/testing/adios2/engine/bp/operations/TestBPWriteReadZfpConfig.cpp
@@ -13,6 +13,18 @@
 
 #include <gtest/gtest.h>
 
+#if defined(_MSC_VER)
+#pragma warning( push )
+//#pragma warning( disable : 4101)
+#elif defined(__GNUC__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wunused-variable"
+
+#elif defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-variable"
+#endif
+
 #define str_helper(X) #X
 #define mystr(X) str_helper(X)
 
@@ -900,3 +912,11 @@ int main(int argc, char **argv)
 
     return result;
 }
+
+#if defined(_MSC_VER)
+#pragma warning( pop )
+#elif defined(__GNUC__)
+#pragma GCC diagnostic pop
+#elif defined(__clang__)
+#pragma clang diagnostic pop
+#endif
diff --git a/testing/adios2/engine/skeleton/TestSkeletonReader.cpp b/testing/adios2/engine/skeleton/TestSkeletonReader.cpp
index cdf30bac5a..05136746a9 100644
--- a/testing/adios2/engine/skeleton/TestSkeletonReader.cpp
+++ b/testing/adios2/engine/skeleton/TestSkeletonReader.cpp
@@ -113,9 +113,11 @@ int main(int argc, char *argv[])
                 adios2::Variable<float> varArray = io.DefineVariable<float>(
                     "myArray", {gndx}, {gndx / (size_t)nproc},
                     {gndx / (size_t)nproc});
+                (void)varArray;
 
                 adios2::Variable<std::string> varSyncString =
                     io.DefineVariable<std::string>("mySyncString");
+                (void)varSyncString;
             }
             else
             {
diff --git a/testing/adios2/engine/staging-common/ParseArgs.h b/testing/adios2/engine/staging-common/ParseArgs.h
index 8f606b2613..d2c1c31605 100644
--- a/testing/adios2/engine/staging-common/ParseArgs.h
+++ b/testing/adios2/engine/staging-common/ParseArgs.h
@@ -76,7 +76,7 @@ static adios2::Params ParseEngineParams(std::string Input)
     return Ret;
 }
 
-static void ParseArgs(int argc, char **argv)
+void ParseArgs(int argc, char **argv)
 {
     int bare_arg = 0;
     while (argc > 1)
diff --git a/testing/adios2/interface/TestADIOSDefineAttribute.cpp b/testing/adios2/interface/TestADIOSDefineAttribute.cpp
index 4ae737af9a..eeb4f30f5f 100644
--- a/testing/adios2/interface/TestADIOSDefineAttribute.cpp
+++ b/testing/adios2/interface/TestADIOSDefineAttribute.cpp
@@ -749,7 +749,7 @@ TEST_F(ADIOSDefineAttributeTest, VariableException)
                          "myVar1", separator),
                      std::invalid_argument);
 
-        auto var = io.DefineVariable<int>("myVar1");
+        io.DefineVariable<int>("myVar1");
 
         EXPECT_NO_THROW(
             io.DefineAttribute<std::string>("Hello Value", "Value", "myVar1"));
diff --git a/testing/adios2/interface/TestADIOSInterfaceWrite.cpp b/testing/adios2/interface/TestADIOSInterfaceWrite.cpp
index 631f592393..99c6180217 100644
--- a/testing/adios2/interface/TestADIOSInterfaceWrite.cpp
+++ b/testing/adios2/interface/TestADIOSInterfaceWrite.cpp
@@ -7,6 +7,19 @@
 
 #include <gtest/gtest.h>
 
+#if defined(_MSC_VER)
+#pragma warning( push )
+//#pragma warning( disable : 4101)
+#elif defined(__GNUC__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wunused-variable"
+
+#elif defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-variable"
+#endif
+
+
 class ADIOSInterfaceWriteTest : public ::testing::Test
 {
 public:
@@ -634,3 +647,11 @@ int main(int argc, char **argv)
 
     return result;
 }
+
+#if defined(_MSC_VER)
+#pragma warning( pop )
+#elif defined(__GNUC__)
+#pragma GCC diagnostic pop
+#elif defined(__clang__)
+#pragma clang diagnostic pop
+#endif
diff --git a/testing/adios2/performance/manyvars/TestManyVars.cpp b/testing/adios2/performance/manyvars/TestManyVars.cpp
index cf8c1e22c3..93e0d4bdf2 100644
--- a/testing/adios2/performance/manyvars/TestManyVars.cpp
+++ b/testing/adios2/performance/manyvars/TestManyVars.cpp
@@ -187,7 +187,7 @@ class TestManyVars : public ::testing::TestWithParam<RunParams>
             digit++;
         }
 
-        char fmt[16];
+        char fmt[32];
         sprintf(fmt, "v%%%d.%dd", digit, digit);
         for (size_t i = 0; i < NVARS; i++)
         {
diff --git a/testing/adios2/xml/TestXMLConfig.cpp b/testing/adios2/xml/TestXMLConfig.cpp
index a6f5b70ed8..01e1ca2195 100644
--- a/testing/adios2/xml/TestXMLConfig.cpp
+++ b/testing/adios2/xml/TestXMLConfig.cpp
@@ -7,6 +7,18 @@
 
 #include <gtest/gtest.h>
 
+#if defined(_MSC_VER)
+#pragma warning( push )
+//#pragma warning( disable : 4101)
+#elif defined(__GNUC__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wunused-variable"
+
+#elif defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-variable"
+#endif
+
 #define str_helper(X) #X
 #define str(X) str_helper(X)
 
@@ -143,3 +155,11 @@ int main(int argc, char **argv)
 
     return result;
 }
+
+#if defined(_MSC_VER)
+#pragma warning( pop )
+#elif defined(__GNUC__)
+#pragma GCC diagnostic pop
+#elif defined(__clang__)
+#pragma clang diagnostic pop
+#endif
diff --git a/testing/adios2/yaml/TestYAMLConfig.cpp b/testing/adios2/yaml/TestYAMLConfig.cpp
index 1473b33e87..9f0bd27d06 100644
--- a/testing/adios2/yaml/TestYAMLConfig.cpp
+++ b/testing/adios2/yaml/TestYAMLConfig.cpp
@@ -7,6 +7,18 @@
 
 #include <gtest/gtest.h>
 
+#if defined(_MSC_VER)
+#pragma warning( push )
+//#pragma warning( disable : 4101)
+#elif defined(__GNUC__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wunused-variable"
+
+#elif defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-variable"
+#endif
+
 #define str_helper(X) #X
 #define str(X) str_helper(X)
 
@@ -113,3 +125,12 @@ int main(int argc, char **argv)
 
     return result;
 }
+
+
+#if defined(_MSC_VER)
+#pragma warning( pop )
+#elif defined(__GNUC__)
+#pragma GCC diagnostic pop
+#elif defined(__clang__)
+#pragma clang diagnostic pop
+#endif