Re: [PATCH] ASoC: core: Fix Sparse incompatible types warning

From: Lars-Peter Clausen
Date: Wed Apr 09 2014 - 16:31:20 EST


On 04/09/2014 10:25 PM, Mark Brown wrote:
On Wed, Apr 09, 2014 at 01:30:47PM +0200, Lars-Peter Clausen wrote:
On 04/09/2014 01:12 PM, Krzysztof Kozlowski wrote:
On Åro, 2014-04-09 at 12:57 +0200, Lars-Peter Clausen wrote:
On 04/09/2014 09:21 AM, Krzysztof Kozlowski wrote:

- buf_size = min(count, (sizeof(buf)-1));
+ buf_size = min(count, (size_t)(sizeof(buf)-1));

But shouldn't the type of sizeof already be size_t?

Hmmm... yes it should. It looks like a false positive from Sparse so the
commit message should be rather "Suppress" than "Fix".

I'm pretty sure it is a bug in sparse, we shouldn't suppress those, but
rather fix them in sparse itself.

Either that or there's something else going on that hasn't been properly
understood. The above just looks completely bogus.


I had a look at the sparse code and the problem is that it sets the default return type of sizeof according to the type of the host it was compiled on (either unsigned int or unsigned long). It can be overwritten by switches like -m32, but of course wont work when cross compiling. So if your host system is 64bit, but your target system is 32bit you'll get that warning.

- Lars
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