On Wed, Dec 21, 2016 at 3:02 PM, Derek Foreman <der...@osg.samsung.com> wrote: > On 21/12/16 10:45 AM, marcel-hollerb...@t-online.de wrote: >> On Wed, Dec 21, 2016 at 05:33:20PM +0100, Stefan Schmidt wrote:
[snip] > Are you asking for an explanation of why floating point comparison with > == in C is bad? This is axiomatic and hardly needs discussion in this > forum. It might be idiomatic, but is not necessarily The Correct Thing(tm). The assignment case being one example, another one being actually knowing the correct delta to compare to. > I haven't seen that suggested by anyone, probably because it's a bad idea. > >> Little side note: Claiming that you have to know a codebase for changing >> a==b to EINA_DBL_CMP(a,b) is NOT realistic :) > > ENOUGH of this! I've been trying to just sit this one out, but come on! [snip] > Further, there may be cases where we intentionally only want a > comparison to trigger if the value is *exact* (as in, has been set that > way by assignment). This could be the case in matrix math operations. This is the case with C++ test suite, either directly or indirectly by template instantiations, e.g. when comparing two containers of floats. > These warnings aren't trivially resolved by people with no familiarity > with the code. It does seem to be the case, and the warning itself might actually require worse code to avoid it. I don't like it. [snip] > Floating point comparison in C leads to very difficult to diagnose bugs. > > I'm strongly in favor of turning this warning back on immediately. Then only where it makes sense please. Even then, I don't think forcing the whole community to deal with this is the right approach. I'm with Stefan here, first work in a branch, and then when the number of warnings is actually reasonable, push to master. > This whole debate makes no sense. > > Thanks, > Derek Regards, -- Felipe Magno de Almeida ------------------------------------------------------------------------------ Developer Access Program for Intel Xeon Phi Processors Access to Intel Xeon Phi processor-based developer platforms. With one year of Intel Parallel Studio XE. Training and support from Colfax. Order your platform today.http://sdm.link/intel _______________________________________________ enlightenment-devel mailing list enlightenment-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/enlightenment-devel
