Add detection of mismatches usages of MEM_new/MEM_freeN.

This commit will error (and abort if enabled) when trying to call
`MEM_freeN` (and related `MEM_dupallocN`, `MEM_reallocN` and
`MEM_recallocN` functions) with a pointer created the C++ way (i.e.
through `MEM_new`, or the guardedalloc-overloaded `new` operator).

To do so, it adds internal use only implementations for `malloc_alligned`
and `free`, which take an extra parameter indicating whether they are
dealing with data created/deleted the 'C++ way' (using `new`/`delete`
and similar).

The cpp-created data are flagged with the new
`MEMHEAD_FLAG_FROM_CPP_NEW`, either in the lower two-bytes len value for
lockfree allocator, or as a new flag member of the guarded allocator
header data.

The public `MEM_new`/`MEM_delete` template functions, and the
guardedalloc-overloaded versions of `new`/`delete` operators are updated
accordingly.

These changes have been successfully tested both with and without
`WITH_CXX_GUARDEDALLOC`.

NOTE: A lot of mismatches have already been fixed in `main` before merging
this change. There are likely some less easy to trigger ones still in our
codebase though.

Pull Request: https://projects.blender.org/blender/blender/pulls/123740

intern/guardedalloc/intern/mallocn_intern_function_pointers.hh

@@ -0,0 +1,30 @@
+/* SPDX-FileCopyrightText: 2024 Blender Authors
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later */
+
+/** \file
+ * \ingroup intern_mem
+ */
+
+#pragma once
+
+namespace mem_guarded::internal {
+
+enum class AllocationType {
+  /** Allocation is handled through 'C type' alloc/free calls. */
+  ALLOC_FREE,
+  /** Allocation is handled through 'C++ type' new/delete calls. */
+  NEW_DELETE,
+};
+
+/** Internal implementation of #MEM_freeN, exposed because #MEM_delete needs access to it. */
+extern void (*mem_freeN_ex)(void *vmemh, AllocationType allocation_type);
+
+/** Internal implementation of #MEM_mallocN_aligned, exposed because #MEM_new needs access to it.
+ */
+extern void *(*mem_mallocN_aligned_ex)(size_t len,
+                                       size_t alignment,
+                                       const char *str,
+                                       AllocationType allocation_type);
+
+}  // namespace mem_guarded::internal