[ub] [c++std-ext-14592] Re: Re: Sized integer types and char bits

John Regehr regehr at cs.utah.edu
Sun Oct 27 17:08:26 CET 2013


>> Wow-- anyone care to guess what fraction of existing C programs run
>> correctly under these conditions?
> Define correctly.

A conforming program could be said to run correctly under a 
non-conforming C implementation if some test suite fails to find 
anything wrong with the program.

For example it's not uncommon to see programs that use 
1<<(sizeof(int)*CHAR_BIT-1) instead of INT_MIN. Any such program would 
be highly unlikely to run correctly on the 36-bit ones complement C 
implementation.

John


More information about the ub mailing list