tree ebe8965e3c4337c5287daac4cb51c21e83239fc2
parent eb00457d624c70a2492c319e7e05ed7e067b2794
author Julia Lawall <julia@diku.dk> 1248711325 +0200
committer Felix Blyakher <felixb@sgi.com> 1251747982 -0500

fs/xfs: Correct redundant test

bp was tested for NULL a few lines before, followed by a return, and there
is no intervening modification of its value.

A simplified version of the semantic match that finds this problem is as
follows: (http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@r exists@
local idexpression x;
expression E;
position p1,p2;
@@

if (x == NULL || ...) { ... when forall
   return ...; }
... when != \(x=E\|x--\|x++\|--x\|++x\|x-=E\|x+=E\|x|=E\|x&=E\|&x\)
(
*x == NULL
|
*x != NULL
)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Acked-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>