Activate tests for new ADIOS2 schema on MSVC

This also fixes broken array placement new in MSVC

Author: franzpoeschel

src/IO/ADIOS/ADIOS2PreloadAttributes.cpp

@@ -28,6 +28,7 @@
 #include "openPMD/IO/ADIOS/ADIOS2Auxiliary.hpp"
 #include "openPMD/auxiliary/StringManip.hpp"
 
+#include <cstddef>
 #include <cstdlib>
 #include <iostream>
 #include <numeric>
@@ -52,7 +53,7 @@ namespace detail
             constexpr size_t
             operator()( Args &&... ) const
             {
-                return 0;
+                return alignof(std::max_align_t);
             }
         };
 
@@ -102,7 +103,15 @@ namespace detail
                 {
                     numItems *= extent;
                 }
-                new( dest ) T[ numItems ]{};
+                /*
+                 * MSVC does not like placement new of arrays, so we do it
+                 * in a loop instead.
+                 * https://developercommunity.visualstudio.com/t/c-placement-new-is-incorrectly-compiled/206439
+                 */
+                for( size_t i = 0; i < numItems; ++i )
+                {
+                    new( dest + i ) T();
+                }
                 location.destroy = buffer;
                 engine.Get( var, dest, adios2::Mode::Deferred );
             }

test/SerialIOTest.cpp

@@ -3235,12 +3235,6 @@ TEST_CASE( "bp4_steps", "[serial][adios2]" )
         }
     }
     )";
-    /*
-     * @todo Activate these tests for Windows as soon as we bump the required
-     *       ADIOS2 version to 2.7.0. Read here:
-     *       https://github.com/openPMD/openPMD-api/pull/813#issuecomment-762235260
-     */
-#ifndef _WIN32
     // sing the yes no song
     bp4_steps( "../samples/newlayout_bp4steps_yes_yes.bp", useSteps, useSteps );
     bp4_steps(
@@ -3249,7 +3243,6 @@ TEST_CASE( "bp4_steps", "[serial][adios2]" )
         "../samples/newlayout_bp4steps_yes_no.bp", useSteps, dontUseSteps );
     bp4_steps(
         "../samples/newlayout_bp4steps_no_no.bp", dontUseSteps, dontUseSteps );
-#endif
 }
 #endif