Re: [libvirt] [PATCH 4/4] virFree: Check const correctness

Up to now it's possible to do something like this: const char *ptr; ptr = strdup("my example string"); VIR_FREE(ptr); The problem is, const char * pointers should not be modified (and freeing them is kind of modification). We should avoid this. A little trick is used: assigning a const pointer into 'void *' triggers compiler warning about discarding 'const' qualifier from pointer. So the virFree() function gains new dummy argument, that is not touched anyhow, just fulfills the const correctness check duty. Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com&gt; --- src/util/viralloc.c | 6 ++++-- src/util/viralloc.h | 20 ++++++++++++++++---- src/xenapi/xenapi_utils.c | 2 +- 3 files changed, 21 insertions(+), 7 deletions(-) diff --git a/src/util/viralloc.c b/src/util/viralloc.c index be9f0fe..0134e67 100644 --- a/src/util/viralloc.c +++ b/src/util/viralloc.c

@@ -569,13 +569,15 @@ int virAllocVar(void *ptrptr, /** * virFree: + * @ptr: dummy pointer to check const correctness * @ptrptr: pointer to pointer for address of memory to be freed * * Release the chunk of memory in the pointer pointed to by * the 'ptrptr' variable. After release, 'ptrptr' will be * updated to point to NULL. */ -void virFree(void *ptrptr) +void virFree(void *ptr ATTRIBUTE_UNUSED, + void *ptrptr)