🚀 go-pugleaf

I think I've discovered some errors in Microsoft Visual C++ 2.0 compiler.

1) Suppose we want to overload global 'operator new':

void* operator new (size_t size, MemoryAllocator* palloc)
{
    // Allocate memory using special allocator
    return palloc->alloc (size);
}

How to delete object allocated by this function?
We can't overload 'operator delete' (according to ARM 5.3.4, 12.5).
We must write something like this:

void Delete_SomeClass (SomeClass* p, MemoryAllocator* palloc)
{
    p->~SomeClass ();    // direct destructor call
    palloc->free (p);    // free memory
}

It works, but it is too tiresome to write such function for every class.
A better way is to use template function:

template <class Type>
void Delete (Type* p, MemoryAllocator* palloc)
{
    p->~Type ();         // direct destructor call - is it allowed here?
    palloc->free (p);    // free memory
}

But if I try to write

    MemoryAllocator alloc;
    SomeClass* p = new (&alloc) SomeClass;
    Delete (p, &alloc);

then compiler writes something like
filename(line#) : error C2300: 'SomeClass' : class does
not have a destructor called '~Type'

Is it an error of compiler? Or direct call of destructor
in template is not allowed? I haven't found something
about it in ARM.


2) Again, let's overload global 'operator new' with default parameter:

void* operator new (size_t size, MemoryAllocator* palloc = NULL)
{
    return palloc ? palloc->alloc (size) : malloc (size);
}

If I write now

    char* p = new char [100];

then compiler (it seems) must invoke operator new (100, NULL). But when I've
inspected assembler listing, I discovered that compiler invokes standard
library version of 'operator new' rather than overloaded one.
To correct it, I have to write

void* operator new (size_t size, MemoryAllocator* palloc)
{
    return palloc ? palloc->alloc (size) : malloc (size);
}
void* operator new (size_t size)
{
    return operator new (size, NULL);
}

Now it works OK. Is it also a compiler error?

Alex Bobkov.
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