Bug 388787 - Support for C++17 new/delete

These over-aligned new and delete operators were added in C++ 17.

memcheck/tests/cxx17_aligned_new.cpp

@@ -0,0 +1,48 @@
+#include <cstdlib>
+#include <new>
+#include <iostream>
+
+class alignas(64) MyClass {
+public:
+    int i;
+};
+
+class OrdinaryClass {
+public:
+    int i;
+};
+
+int main() {
+    // unsized versions
+    MyClass* myClass = new MyClass;
+    operator delete(myClass, std::align_val_t(64U));
+
+    MyClass* myClass5 = new MyClass[5];
+    operator delete [](myClass5, std::align_val_t(64U));
+
+    // sized versions
+    myClass = new MyClass();
+    operator delete(myClass, 64U, std::align_val_t(64U));
+
+    myClass5 = new MyClass[5];
+    operator delete [](myClass5, 320U, std::align_val_t(64U));
+
+    MyClass* myClassNt = new (std::nothrow) MyClass;
+    operator delete(myClassNt, std::align_val_t(64U),  std::nothrow);
+
+    MyClass* myClass5Nt = new (std::nothrow) MyClass[5];
+    operator delete [](myClass5Nt, std::align_val_t(64U), std::nothrow);
+
+    OrdinaryClass* oClass = new OrdinaryClass;
+    // this is a limitation, VG does not use enough bits
+    // to tell apart aligned and unaligned allocations
+    // so new/aligned delete is not a mismatch
+    operator delete(oClass, std::align_val_t(64U));
+    oClass = new (std::nothrow) OrdinaryClass;
+    delete oClass;
+    oClass = new OrdinaryClass[5];
+    delete [] oClass;
+    oClass = new (std::nothrow) OrdinaryClass[5];
+    delete [] oClass;
+}
+