Changeset 3a038fa for doc/theses/mubeen_zulfiqar_MMath/allocator.tex

Timestamp:

Feb 23, 2022, 10:31:12 AM (3 years ago)

Author:

Peter A. Buhr <pabuhr@…>

Branches:

ADT, ast-experimental, enum, master, pthread-emulation, qualifiedEnum

Children:

cc7bbe6

Parents:

f53afafb

Message:

more updates to added text

File:

• doc/theses/mubeen_zulfiqar_MMath/allocator.tex (modified) (1 diff)

doc/theses/mubeen_zulfiqar_MMath/allocator.tex

@@ -118 +118 @@
 We added a few more features and routines to the allocator's C interface that can make the allocator more usable to the programmers. THese features will programmer more control on the dynamic memory allocation.
 
+\subsection{Out of Memory}
+
+Most allocators use @nullptr@ to indicate an allocation failure, specifically out of memory;
+hence the need to return an alternate value for a zero-sized allocation.
+The alternative is to abort a program when out of memory.
+In theory, notifying the programmer allows recovery;
+in practice, it is almost impossible to gracefully when out of memory, so the cheaper approach of returning @nullptr@ for a zero-sized allocation is chosen.
+
+
 \subsection{\lstinline{void * aalloc( size_t dim, size_t elemSize )}}
 @aalloc@ is an extension of malloc. It allows programmer to allocate a dynamic array of objects without calculating the total size of array explicitly. The only alternate of this routine in the other allocators is calloc but calloc also fills the dynamic memory with 0 which makes it slower for a programmer who only wants to dynamically allocate an array of objects without filling it with 0.