On Fri, Apr 22, 2011 at 10:55:04AM -0600, Eric Blake wrote:
On 04/22/2011 10:31 AM, Christophe Fergeau wrote:
-# define VIR_FREE(ptr) virFree(&(ptr)) +# define VIR_FREE(ptr) \ + do { void *check_type = (ptr); virFree(&(check_type)); } while (0)
Not quite. That assigns check_type to NULL, rather than the intended assignment of ptr.
Ooops, indeed. Initially, I didn't change the parameter of virFree, but got "unused variable 'check_type'" warnings from gcc, so I went this way. Using ATTRIBUTE_UNUSED and not changing virFree parameter will indeed work better ;)
I also get more warnings about casting from const to non-const, this can be avoided by making check_type const void *, but maybe these warnings indicate that something that shouldn't be freed is freed.
How many warnings? If it's only a handful, we should start investigating; if it's lots, then I'm not sure how much it buys us.
I get 93 such warnings on a test build, I'll look at a few ones at random and report if that shows real bugs. Christophe