[sane-devel] Check out valgrind

[Petter Reinholdtsen]

Remember a long time ago, when I used Purify to find lots of errors
with SANE?  Now a similar tool is available for all.  Check out
valgrind, <URL:http://developer.kde.org/~sewardj/>.

> Valgrind, an open-source memory debugger for x86-GNU/Linux
> 
> Valgrind is a GPL'd tool to help you find memory-management problems
> in your programs. When a program is run under Valgrind's supervision,
> all reads and writes of memory are checked, and calls to
> malloc/new/free/delete are intercepted. As a result, Valgrind can
> detect problems such as:
> 
>  - Use of uninitialised memory 
>  - Reading/writing memory after it has been free'd 
>  - Reading/writing off the end of malloc'd blocks 
>  - Reading/writing inappropriate areas on the stack 
>  - Memory leaks -- where pointers to malloc'd blocks are lost forever
>  - Passing of uninitialised and/or unaddressible memory to system calls
>  - Mismatched use of malloc/new/new [] vs free/delete/delete []
> 
> Valgrind tracks each byte of memory in the original program with nine
> status bits, one of which tracks addressibility of that byte, while
> the other eight track the validity of the byte.  As a result, it can
> detect the use of single uninitialised bits, and does not report
> spurious errors on bitfield operations.

It only works on linux/x86, but on that platform works just fine. :-)