On Tue, Apr 30, 2019 at 05:33:10AM +0200, Nicholas Mc Guire wrote: > ok - my bad thn - I had assumed that using __force is reasonable > if the handling is correct and its a localized conversoin only > like var = be16_to_cpu(var) which evaded introducing additinal > variables just to have different types but no different function. If compiler can't recognize that in T1 v1; T2 v2; code using v1, but not v2 v2 = f(v1); code using v2, but not v1 it can use the same memory for v1 and v2, file a bug against the compiler. Or stop using that toy altogether - that kind of optimizations is early 60s stuff and any real compiler will handle that. Both gcc and clang certainly do handle that. Another thing they handle is figuring out that be16_to_cpu() et.al. are pure functions, so f(be16_to_cpu(n)); no modifications of n g(be16_to_cpu(n)); doesn't need to have le16_to_cpu recalculated. IOW, that particular code could as well have been dev_info(dev, "Fieldbus type: %04X", be16_to_cpu(fieldbus_type)); ... cd->client->fieldbus_type = be16_to_cpu(fieldbus_type); ... not that there's much sense keeping ->fieldbus_type in host-endian, while we are at it. _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
