Re: cppcheck run against 1.27

[chris ahrendt]

Marcus Meissner wrote:
> On Fri, Aug 07, 2009 at 06:36:36PM -0700, chris ahrendt wrote:
> > [../wine-git/dlls/ntdll/server.c:802]: (error) Resource leak: fd
>
> I do not fully understand the code (keep fd open to have to lock
> existing?), but it is in a fatal exit path.
> > [../wine-git/tools/fnt2bdf.c:219]: (error) Resource leak: fp
> > [../wine-git/tools/fnt2bdf.c:653]: (error) Resource leak: fd
>
> Fix submitted, seem necessary.
> > [../wine-git/tools/fnt2fon.c:304]: (error) Memory leak: file_lens
>
> Fix submitted, but program is shortlived.
> > [../wine-git/tools/widl/write_msft.c:2540]: (error) Deallocating a 
> > deallocated pointer: fd
>
> I do not understand what it mislikes about it. I think the detection
> is wrong.
> > [../wine-git/tools/winebuild/res16.c:187]: (error) Resource leak: fd
>
> Fix submitted. Small issue though.
> > [../wine-git/tools/winedump/pe.c:1549]: (error) Memory leak: map
>
> Fix submitted. Small issue though.
>
> Ciao, Marcus

here is what its checking for :

Standard checks that are always used

* out of bounds
    * Using 'memfunc' on class
    * Using 'memfunc' on struct that contains a 'std::classname'
    * Class Base which is inherited by class Derived does not have a
      virtual destructor
    * Mismatching allocation and deallocation: varname
    * Memory leak http://en.wikipedia.org/wiki/Memory_leak: varname
    * Resource leak http://en.wikipedia.org/wiki/Resource_leak: varname
    * Deallocating a deallocated pointer: varname
    * Using 'varname' after it is deallocated / released
    * The given size sz is mismatching
    * Invalid radix in call to strtol
      http://en.wikipedia.org/wiki/Strtol or strtoul. Must be 0 or 2-36
    * Overlapping data buffer varname
    * Unsigned division. The result will be wrong.
    * Unusual pointer arithmetic
    * Returning pointer to local array variable
    * Same iterator is used with both container1 and container2
    * Dangerous usage of erase
    * After push_back or push_front, the iterator 'iterator_name' may be
      invalid
    * Wrong assignment of an auto-variable to an effective parameter of
      a function
    * Return of the address of an auto-variable
    * Division by zero
    * STL http://en.wikipedia.org/wiki/Standard_Template_Library:
      check usage of iterators after erase, as erase invalidates the
      iterator
    * STL: check usage of iterators and pointers after push_back and
      push_front. If using a vector the iterator or pointer may become
      invalid.
    * STL: Range checks with iterators should use != instead of <

I have not run it with the following :

Extra checks that you enable with "--all" These checks are not part of 
the standard checking because they produce false positives.

* Array index out of bounds
    * Buffer overrun
    * Dangerous usage of strncat http://en.wikipedia.org/wiki/Strcat,
      possible buffer overrun
    * Memory leak: varname
    * The size argument is given as a char constant

Extra checks that you enable with "--style"

* The class 'classname' has no constructor
    * Member variable not initialized in the constructor
      'classname::varname'
    * Unused private function 'classname::funcname'
    * 'operator=' should return something
    * C-style pointer casting
    * Redundant condition. It is safe to deallocate a NULL pointer
    * Redundant condition. The remove function in the STL will not do
      anything if element doesn't exist
    * Found redundant if condition - 'if (condition);'
    * struct or union member 'structname::varname' is never used
    * Function parameter 'parname' is passed by value. It could be
      passed by reference instead.
    * Redundant code: Found a statement that begins with type constant
    * Warning - using char variable as array index
    * Warning - using char variable in bit operation
    * Condition is always truefalse

Checks that are enabled when both "--all" and "--style" is given

* Warning: Division with signed and unsigned operators

When giving "--unused-functions"

* The function 'funcname' is never used

I am going to start running with the --all flag going forward.

So the leak with fd cppcheck thinks that you have an exit path that will 
leave the fd allocated still without freeing the resource.

[../wine-git/dlls/ntdll/server.c:802]: (error) Resource leak: fd so this exits without freeing the resource.

[../wine-git/tools/widl/write_msft.c:2540]: (error) Deallocating a 
deallocated pointer: fd - This just means your freeing an already freed 
resource... This is more of a warning than anything

Chris