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

Paul Eggert eggert at cs.ucla.edu
Tue Nov 8 23:39:50 UTC 2022

On 11/8/22 06:28, Clive D.W. Feather via tz wrote:
> You could replace the assignment by a memcpy. Assignment via unsigned
> chars (which is what memcpy does) are exempt from the undefined behaviour.

As I understand it, that exemption is for using memcpy to copy a trap 
representation. There's no similar exemption for using memcpy to copy 
uninitialized data; for example, the following function has undefined 

    int y;
    void f(void) { int x; memcpy(&y, &x, sizeof y); }

If I'm right, we can't get by simply by replacing the assignment with 

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