VC 디버그빌드에서 들어가는 쓰레기값들의 의미

First, I will explain what all these values that you see, like CD, DD, and so forth, mean.

Value Name Description
0xCD : [Clean Memory] Allocated memory via malloc or new but never written by the application.
0xDD : [Dead Memory] Memory that has been released with delete or free. It is used to detect writing through dangling pointers.
0xFD : [Fence Memory] Also known as "no mans land." This is used to wrap the allocated memory (like surrounding it with fences) and is used to detect indexing arrays out of bounds.
0xAB : [Allocated Block?] Memory allocated by LocalAlloc().
0xBAADF00D : [Bad Food] Memory allocated by LocalAlloc() with LMEM_FIXED, but not yet written to.
0xCC : When the code is compiled with the /GZ option, uninitialized variables are automatically assigned to this value (at byte level).

If you take a look at DBGHEAP.C, you can see how some of these values are defined:

static unsigned char _bNoMansLandFill = 0xFD;   /* fill no-man's land with this */
static unsigned char _bDeadLandFill   = 0xDD;   /* fill free objects with this */
static unsigned char _bCleanLandFill  = 0xCD;   /* fill new objects with this */