[fpe] cherry-pick the last commit from the namespace branch and fix a…

… conflict:

"[namespace] in ggtt.sa, fix testmisc.cc and testxxx.cc to use different namespaces
This CONCLUDES the cleanup of namespaces in ggtt.sa: everything builds and runs ok
NB: in debug mode, now runTest succeeds! As intended, this fixes the segfault in #725"

epochX/cudacpp/gg_tt.sa/SubProcesses/testmisc.cc

@@ -25,32 +25,50 @@
 
 #define XTESTID( s ) TESTID( s )
 
+// NB: namespaces mg5amcGpu and mg5amcCpu includes types which are defined in different ways for CPU and GPU builds (see #318 and #725)
+#ifdef __CUDACC__
+namespace mg5amcGpu
+#else
+namespace mg5amcCpu
+#endif
+{
+
 #ifdef MGONGPU_CPPSIMD /* clang-format off */
 #define EXPECT_TRUE_sv( cond ) { bool_v mask( cond ); EXPECT_TRUE( maskand( mask ) ); }
 #else
 #define EXPECT_TRUE_sv( cond ) { EXPECT_TRUE( cond ); }
 #endif /* clang-format on */
 
-inline const std::string
-boolTF( const bool& b )
-{
-  return ( b ? "T" : "F" );
-}
+  inline const std::string
+  boolTF( const bool& b )
+  {
+    return ( b ? "T" : "F" );
+  }
 
 #ifdef MGONGPU_CPPSIMD
-inline const std::string
-boolTF( const bool_v& v )
-{
-  std::stringstream out;
-  out << "{ " << ( v[0] ? "T" : "F" );
-  for( int i = 1; i < neppV; i++ ) out << ", " << ( v[i] ? "T" : "F" );
-  out << " }";
-  return out.str();
-}
+  inline const std::string
+  boolTF( const bool_v& v )
+  {
+    std::stringstream out;
+    out << "{ " << ( v[0] ? "T" : "F" );
+    for( int i = 1; i < neppV; i++ ) out << ", " << ( v[i] ? "T" : "F" );
+    out << " }";
+    return out.str();
+  }
 #endif
 
+}
+
 TEST( XTESTID( MG_EPOCH_PROCESS_ID ), testmisc )
-{
+{  
+#ifdef __CUDACC__
+  using namespace mg5amcGpu;
+#else
+  using namespace mg5amcCpu;
+#endif
+
+  //--------------------------------------------------------------------------
+
   EXPECT_TRUE( true );
 
   //--------------------------------------------------------------------------

epochX/cudacpp/gg_tt.sa/SubProcesses/testxxx.cc

@@ -53,13 +53,9 @@ namespace mg5amcCpu
 TEST( XTESTID( MG_EPOCH_PROCESS_ID ), testxxx )
 {
 #ifdef __CUDACC__
-  auto FPEhandler = mg5amcGpu::FPEhandler;
-  std::string& FPEhandlerMessage = mg5amcGpu::FPEhandlerMessage;
-  int& FPEhandlerIevt = mg5amcGpu::FPEhandlerIevt;
+  using namespace mg5amcGpu;
 #else
-  auto FPEhandler = mg5amcCpu::FPEhandler;
-  std::string& FPEhandlerMessage = mg5amcCpu::FPEhandlerMessage;
-  int& FPEhandlerIevt = mg5amcCpu::FPEhandlerIevt;
+  using namespace mg5amcCpu;
 #endif
   const bool enableFPE = !getenv( "CUDACPP_RUNTIME_DISABLEFPE" );
   if ( enableFPE )
@@ -72,7 +68,6 @@ TEST( XTESTID( MG_EPOCH_PROCESS_ID ), testxxx )
   constexpr fptype toleranceXXXs = std::is_same<fptype, double>::value ? 1.E-15 : 1.E-5;
   // Constant parameters
   constexpr int neppM = MemoryAccessMomenta::neppM; // AOSOA layout
-  using mgOnGpu::neppV;
   constexpr int np4 = CPPProcess::np4;
   const int nevt = 32;         // 12 independent tests plus 20 duplicates (need a multiple of 16 for floats '512z')
   assert( nevt % neppM == 0 ); // nevt must be a multiple of neppM