Debugging with GDB Manual HP WDB v6.3 (5900-2180, August 2012)

set heap-check block-size
num-bytes
Instructs HP WDB to stop the program whenever it tries to
allocate a block larger than num-bytes in size.
set heap-check heap-size
num-size
Instructs HP WDB to stop the program whenever it tries to
increase the program heap by at least num-bytes.
min-heap-size This option reports the heap allocations that exceed the
specified number <num> of bytes based on the cumulative
number of bytes that are allocated at each call-site, which
is inclusive of multiple calls to malloc at a particular call
site.
set heap-check watch
address
Stops the program whenever a block at a specified address
is allocated or deal- located.
set heap-check null-check
[N | random]
Force malloc to return NULL after N or random number
of invocations of malloc. Use set heap-check
random-range N and set heap-check seed-value
N to define the seed value and range for random number
calculation. Useful for simulating out-of-memory situations.
set heap-check
null-check-size N
Force malloc to return NULL after N bytes have been
allocated by the program.
catch nomem Allows the user to get control of an out-of-memory event.
The user can step through once the nomem event is caught
to see whether the out-of-memory event is handled correctly.
set heap-check free [on |
off]
When set to on, forces HP WDB to stop the program when
it detects a call to free() with an improper argument, a
call to realloc() that does not point to a valid currently
allocated heap block, or a call to free a block of memory,
which has been corrupted. Refer set heap-check
bounds for details on detecting memory corruption.
set heap-check string [on
| off]
Toggles validation of calls to strcpy, strncpy, memcpy,
memccpy, memset, memmove, bzero, and, bcopy. HP
WDB 5.6 and later versions of the debugger also validates
calls to strcat and strncat.
NOTE: HP WDB 6.0 and later versions of the debugger
improves performance of memory debugging when the
string option is set for 32-bit applications on HP-UX 11i
v2 and later on Itanium systems. However, the performance
degrades for 64-bit applications on HP-UX 11i v2 and later
on Itanium systems.
set heap-check bounds [on
| off]
Allocates extra space at the beginning and end of a heap
block during allocation and fills it with a specific pattern.
When blocks are freed, HP WDB verifies whether these
patterns are intact. If they are corrupted, an under flow or
over- flow must have occurred and HP WDB reports the
problem. This option increases the program's memory
requirements.
set heap-check scramble [on
| off]
Scrambles a memory block and overwrites it with a specific
pattern when it is allocated or deallocated. This change to
the memory contents increases the chance that erroneous
behaviors, such as attempting to access space that is freed
or depending on initial values of malloc() blocks, cause
the program to fail.
14.10 Debugging Memory Problems 123