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Re: GCC turns &~ into | due to undefined bit-shift without warning


On 2019-03-12 21:56:59 +0100, David Brown wrote:
> I disagree.  To generate an unconditional error (rejecting the program), the
> compiler would need such proof - such as by tracing execution from main().
> But to generate a warning activated specifically by the user, there is no
> such requirement.  It's fine to give a warning based on the code written,
> rather than on code that the compiler knows without doubt will be executed.

There's already a bug about spurious warnings on shift counts:

  https://gcc.gnu.org/bugzilla/show_bug.cgi?id=4210

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