Setting a breakpoint on malloc_printf
Setting a breakpoint on malloc_printf
- Subject: Setting a breakpoint on malloc_printf
- From: Justin Greenfield <email@hidden>
- Date: Tue, 24 Feb 2004 10:20:53 -0600
I've got a terribly insidious memory smashing bug in a multi-threaded
app that I am trying to track down. I have been beating my head on
this for much, much too long now. I am beyond desperate and I my
progress has slowed to a crawl.
From the MallocDebug help:
Tracking down stale pointers and writes to freed memory
The second example -- holding on to an out of date pointer -- can also
be detected using MallocDebug. MallocDebug finds writes to freed
memory by erasing memory when it is freed, overwriting the contents of
the buffer with the hexadecimal value 0x55. MallocDebug then watches
for changes to that memory on each call to free. When it finds memory
has been smashed, it prints a warning to the console:
MallocDebug: target application recently wrote to freed malloc'd
memory at: 0x194f808, suggesting it didn't realize the memory had been
freed
This shows that a memory smasher exists; by putting a break point on
malloc_printf, the function that prints the error, you can find what
point in your code might be near the smash.
My problem is, I absolutely cannot cause a breakpoint to fire on
malloc_printf when I get these errors printed. I am on 10.3 using
xcode 1.1. I tried going to the breakpoints window, clicking "New
breakpoint" and entering "malloc_printf" but it never fires. I started
gdb in a terminal window and tried "fb malloc_printf" and it never
fires.
If anybody has the slightest idea what to do differently to find this
bug, I would be eternally grateful. I have run out of ideas and
options.
Justin
_______________________________________________
xcode-users mailing list | email@hidden
Help/Unsubscribe/Archives: http://www.lists.apple.com/mailman/listinfo/xcode-users
Do not post admin requests to the list. They will be ignored.