[tz] Minor (unimportant really) technical UB bug in strftime() ?

Paul Eggert eggert at cs.ucla.edu
Thu Nov 10 00:29:18 UTC 2022

On 11/9/22 15:34, Guy Harris via tz wrote:
> Does the C specification allow for a C implementation on a hypothetical load-store architecture machine in which:
> 	a byte is 8 bits plus an "initialized bit";
> 	the "uninitialize" instruction has a memory-location operand, and clears the initialized bit;
> 	a store instruction set the initialized bit on all bytes to which it stores;
> 	a load instruction traps if any of the bytes from which it's loading doesn't have the initialized bit set?

No, not if memcpy is implemented via load+store. The C standard says 
memcpy is supposed to work even if its source bytes are uninitialized. 
(This was news to me until today, and I'm not a fan of this part of the 

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