On Mon, Jan 29, 2018 at 12:33 PM, Greg KH <greg@xxxxxxxxx> wrote: > On Mon, Jan 29, 2018 at 12:16:19PM -0500, Jeffrey Walton wrote: >> ... >> It would be nice if they moved away from UB and implementation defined >> behvior, but sometimes the political problems are heavier than the >> technical solutions. > > What do you mean by this? What "UB" does the kernel rely on that > prevents compilers from properly building it? We do have some pretty > strict requirements in the kernel for a compiler, but anything "odd" is > usually just a bug and we are always willing to take patches to fix > them. https://groups.google.com/forum/#!topic/linux.kernel/-VzG6FWZiy8 and https://www.spinics.net/lists/linux-crypto/msg19466.html . I found the first one from 2013 amusing: JW >> According to Section 5.8, "Shift Operators" of JW >> http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2798.pdf: JW >> "The operands shall be of integral or enumeration type ... CL > The kernel doesn't try to be fully standard conformant. The second one from 2016 was disappointing. It suggested a standards compliant rotate that was constant time for the linux-crypto folks. That was rejected by some: PA >> So you are actually saying outright that we should sacrifice *actual* PA >> portability in favor of *theoretical* portability? What kind of PA >> twilight zone did we just step into?! Its kind of like I said... the political problems are harder than the technical solutions. Jeff _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
