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4 debugging memory in interactive mode, 1 commands for interactive memory debugging – HP gnu source-level debugger 5992-4701 User Manual

Page 159

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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-block corruption 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)

.

14.10.4 Debugging 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 [on|off]

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

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