On Thu, May 10, 2001 at 07:22:13AM -0400, Uncle George wrote:
> Malloc/free bugs are never that simple. Generally u are freeing up the (same)
> pointer for a second time, or u stepped over the allocation size and onto a malloc
> header. How do u know which one, by eliminating the possibility of freeing the
> same pointer twice ( which for me has been to print out all the ptr's given & put
> back by the malloc routines )
> /gat
>
I agree to Rick, they are 'quite' easy ...
For two reasons: first it is rather well defined
which function calls are involved and second there are so
many utilities waiting for you to be used for that
purpose.
It took me a few seconds to produce the following printout.
Note that I mentioned this fine tool some weeks ago on some
of our lists here. And back to the discussion: if you
get some other strange problems within LessTif like
something never shwoing up or major visual problems
there is no tool which will help you. I guess that's
what Rick meant.
BTW, I haven't checked yet whether this info is really
sufficient to cure the bug; if you read lesstif-commits
and don't see an entry within the next minutes it wasn't
enough for now ;-)
.--------------------------------------------------------------------------.
|================ ccmalloc-0.3.4 (C) 1997-2000 Armin Biere ================|
+--------------------------------------------------------------------------+
| executable = test1 |
| startup file = .ccmalloc |
| log file = Log |
| start time = Thu May 10 13:33:03 2001 |
| operating system = Linux 2.0.36 i586 |
+--------------------------------------------------------------------------+
| only-count = 0 keep-deallocated-data = 1 |
| check-interval = 0 check-free-space = 0 |
| check-start = 0 file-info = 1 |
| chain-length = 0 additional-line = 1 |
| check-underwrites = 0 print-addresses = 0 |
| check-overwrites = 0 print-on-one-line = 0 |
| sort-by-wasted = 1 sort-by-size = 1 |
| # only-log-chain = 0 continue = 0 |
| # dont-log-chain = 0 statistics = 0 |
| debug = 1 library-chains = 0 |
| load-dynlibs = 1 align-8-byte = 0 |
| only-wasting-alloc= 1 |
`--------------------------------------------------------------------------'
*** free() called twice for block at 0x08645af0 of size 256
*** it was allocated at
*** |
*** | 0x08049df5 in <main>
*** | at
/home/mai/compile/lesstif/lesstif/lib/Xlt/tests/FontChooser/test1.c:26
*** |
*** | 0x40223464 in <XtRealizeWidget>
*** |
*** | 0x40223375 in <RealizeWidget>
*** |
*** | 0x402231bb in <RealizeWidget>
*** |
*** | 0x4003778a in <Realize>
*** | at
/home/mai/compile/lesstif/lesstif/lib/Xlt/lib/FontChooser.c:370
*** |
*** | 0x402108a3 in <XtMalloc>
*** |
*** `---> 0x08053fa2 in <malloc>
*** at src/wrapper.c:284
***
*** and already freed at
*** |
*** | 0x08049df5 in <main>
*** | at
/home/mai/compile/lesstif/lesstif/lib/Xlt/tests/FontChooser/test1.c:26
*** |
*** | 0x40223464 in <XtRealizeWidget>
*** |
*** | 0x40223375 in <RealizeWidget>
*** |
*** | 0x402231bb in <RealizeWidget>
*** |
*** | 0x400379e8 in <Realize>
*** | at
/home/mai/compile/lesstif/lesstif/lib/Xlt/lib/FontChooser.c:421
--
Alexander Mai
[EMAIL PROTECTED]
