Am 30.06.2016 13:16, schrieb Joe Perches:
> On Thu, 2016-06-30 at 10:50 +0300, Dan Carpenter wrote:
>> On Wed, Jun 29, 2016 at 10:05:53AM -0700, H. Peter Anvin wrote:
>>> On 06/29/16 07:42, Dan Carpenter wrote:
>>>>>> and | behave basically the same here but || is intended. It causes a
>>>> static checker warning to mix up bitwise and logical operations.
>>>>
>>>> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
>>>>
>>>> diff --git a/arch/x86/crypto/sha256-mb/sha256_mb.c b/arch/x86/crypto/sha256-mb/sha256_mb.c
> []
>>>> @@ -299,7 +299,7 @@ static struct sha256_hash_ctx *sha256_ctx_mgr_submit(struct sha256_ctx_mgr *mgr,
>>>> * Or if the user's buffer contains less than a whole block,
>>>> * append as much as possible to the extra block.
>>>> */
>>>> - if ((ctx->partial_block_buffer_length) | (len < SHA256_BLOCK_SIZE)) {
>>>> + if ((ctx->partial_block_buffer_length) || (len < SHA256_BLOCK_SIZE)) {
>>>> /* Compute how many bytes to copy from user buffer into
>>>> * extra block
>>>> */
>>>>
>>> As far as I know the | was an intentional optimization, so you may way
>>> to look at the generated code.
>> I know how the rules work. I just thought it looked more like a typo
>> than an optimization. It's normally a typo. It's hard to tell the
>> intent.
>
> The compiler could potentially emit the same code when
> optimizing but at least gcc 5.3 doesn't.
>
> It's probably useful to add a comment for the specific intent
> here rather than change a potentially useful static checker.
>
perhaps we can agree not to play tricks with a compiler.
Everything may be true for a certain version of CC but the next compiler is different.
just my 2 cents,
wh
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