On Mon, Nov 5, 2012 at 12:50 PM, Wolfgang Denk wd@denx.de wrote:
Dear Pavel,
In message 20121105200340.GA15821@xo-6d-61-c0.localdomain you wrote:
/* Append length in bits and transform */
ctx->in32[14] = ctx->bits[0];ctx->in32[15] = ctx->bits[1];
memcpy(ctx->in + 14 * sizeof(__u32), ctx->bits, 2 *sizeof(__u32));
This makes the code actually unreadable. Please add at least a comment what this is doing.
Actually I think this shoul dbe split into two memcpy commands, using the addresses of the respective array elements directly, without such manual pointer arithmetics.
I guess bigger question is: why does gcc miscompile that, and is it guaranteed that it will not miscompile the memcpy?
I did not see Simon mentioning anythin about incorrect compilation. My understanding was that it's just the usual "dereferencing type-punned pointer" warnings issue.
Yup, it's a compilation warning. issue. (but warnings being treated as errors.)
Simon, what was the actual problem this was supposed to fix?
Best regards,
Wolfgang Denk
-- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@denx.de Let's say the docs present a simplified view of reality... :-) - Larry Wall in 6940@jpl-devvax.JPL.NASA.GOV