Re: [PATCH] objtool: Fix calloc call for new -Walloc-size

[Josh Poimboeuf]

On Tue, Nov 07, 2023 at 08:55:00PM +0000, Sam James wrote:
> GCC 14 introduces a new -Walloc-size included in -Wextra which errors out
> like:
> ```
> check.c: In function ‘cfi_alloc’:
> check.c:294:33: error: allocation of insufficient size ‘1’ for type ‘struct cfi_state’ with size ‘320’ [-Werror=alloc-size]
>   294 |         struct cfi_state *cfi = calloc(sizeof(struct cfi_state), 1);
>       |                                 ^~~~~~
> ```
> 
> The calloc prototype is:
> ```
> void *calloc(size_t nmemb, size_t size);
> ```
> 
> So, just swap the number of members and size arguments to match the prototype, as
> we're initialising 1 struct of size `sizeof(struct ...)`. GCC then sees we're not
> doing anything wrong.
> 
> Signed-off-by: Sam James <sam@xxxxxxxxxx>
> ---
>  tools/objtool/check.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/tools/objtool/check.c b/tools/objtool/check.c
> index e94756e09ca9..548ec3cd7c00 100644
> --- a/tools/objtool/check.c
> +++ b/tools/objtool/check.c
> @@ -291,7 +291,7 @@ static void init_insn_state(struct objtool_file *file, struct insn_state *state,
>  
>  static struct cfi_state *cfi_alloc(void)
>  {
> -	struct cfi_state *cfi = calloc(sizeof(struct cfi_state), 1);
> +	struct cfi_state *cfi = calloc(1, sizeof(struct cfi_state));
>  	if (!cfi) {
>  		WARN("calloc failed");
>  		exit(1);

Thanks!

Acked-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>

Peter are you able to grab this or should I put it in my tree first?

-- 
Josh