HP WDB offers the following memory-debugging capabilities:

•Reports memory leaks

•Reports heap allocation profile

•Stops program execution if bad writes occur with string operations such as strcpy and memcpy

•Stops program execution when freeing unallocated or de-allocated blocks

•Stops program execution when freeing a block if bad writes occur outside block boundary

•Stops program execution conditionally based on whether a specified block address is allocated or de-allocated

•Scrambles previous memory contents at malloc() and free() calls

•Simulates and detects out-of-memory event errors

•Detects dangling pointers and dangling blocks

•Detects in-blockcorruption of freed blocks

•Specifies the amount of guard bytes for every block of allocated memory

•Displays the run time type information for C++ polymorphic objects

You can use any of the following methods to identify memory problems:

•See “Debugging Memory in Interactive Mode” (page 159).

•See “Debugging Memory in Batch Mode” (page 164).

•See “Debugging Memory Interactively After Attaching to a Running Process” (page 171).

14.10.4Debugging Memory in Interactive Mode

This section describes the various commands which help in debugging memory problems when the debugger is used in the interactive mode.

14.10.4.1 Commands for interactive memory debugging

To debug memory problems, use these commands:

set heap-check [onoff]

This toggles the capability for detection of leaks,

 

heap profiles, bounds checking, and checking for

 

double free.

info heap

Displays a heap report, listing information such

 

as the start of heap, end of heap, heap size, heap

 

allocations, size of blocks, and number of

 

instances. The report shows heap usage at the

 

point you use the info heap command. The

 

report does not show allocations that have

 

already been freed. For example, if you make

 

several allocations, free them all, and then you

14.10 Debugging Memory Problems 159