New/delete VS malloc/free

REFER:SO

中文社区见到的答案,不提也罢

new/delete

• Allocate/release memory
  1. Memory allocated from 'Free Store'
  2. Returns a fully typed pointer.
  3. new (standard version) never returns a NULL (will throw on failure)
  4. Are called with Type-ID (compiler calculates the size)
  5. Has a version explicitly to handle arrays.
  6. Reallocating (to get more space) not handled intuitively (because of copy constructor).
  7. Whether they call malloc/free is implementation defined.
  8. Can add a new memory allocator to deal with low memory (set_new_handler)
  9. operator new/delete can be overridden legally
  10. constructor/destructor used to initialize/destroy the object

malloc/free

• Allocates/release memory
  1. Memory allocated from 'Heap'
  2. Returns a void*
  3. Returns NULL on failure
  4. Must specify the size required in bytes.
  5. Allocating array requires manual calculation of space.
  6. Reallocating larger chunk of memory simple (No copy constructor to worry about)
  7. They will NOT call new/delete
  8. No way to splice user code into the allocation sequence to help with low memory.
  9. malloc/free can NOT be overridden legally