On 09/28/16 16:41, Jason Merrill wrote: > On Tue, Sep 27, 2016 at 11:10 AM, Bernd Edlinger > <bernd.edlin...@hotmail.de> wrote: >> On 09/27/16 16:42, Jason Merrill wrote: >>> On Tue, Sep 27, 2016 at 10:28 AM, Bernd Edlinger >>> <bernd.edlin...@hotmail.de> wrote: >>>> On 09/27/16 16:10, Florian Weimer wrote: >>>>> * Bernd Edlinger: >>>>> >>>>>>> “0 << 0” is used in a similar context, to create a zero constant for a >>>>>>> multi-bit subfield of an integer. >>>>>>> >>>>>>> This example comes from GDB, in bfd/elf64-alpha.c: >>>>>>> >>>>>>> | insn = INSN_ADDQ | (16 << 21) | (0 << 16) | (0 << 0); >>>>>>> >>>>>> >>>>>> Of course that is not a boolean context, and will not get a warning. >>>>>> >>>>>> Question is if "if (1 << 0)" is possibly a miss-spelled "if (1 < 0)". >>>>>> >>>>>> Maybe 1 and 0 come from macro expansion.... >>>>> >>>>> But what's the intent of treating 1 << 0 and 0 << 0 differently in the >>>>> patch, then? >>>> >>>> I am not sure if it was a good idea. >>>> >>>> I saw, we had code of the form >>>> bool flag = 1 << 2; >>>> >>>> another value LOOKUP_PROTECT is 1 << 0, and >>>> bool flag = 1 << 0; >>>> >>>> would at least not overflow the allowed value range of a boolean. >>> >>> Assigning a bit mask to a bool variable is still probably not what was >>> intended, even if it doesn't change the value. >> >> That works for me too. >> I can simply remove that exception. > > Sounds good. >
Great. Is that an "OK with that change"? Bernd.
