Comment 2 for bug 1991765

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Andrew Johnson (anj) wrote :

The original change (released 7½ years ago) was to properly support 32-bit raw values as you requested in but without triggering UB, which modern compiler optimizers love to rely on to break previously-working-but-non-portable code.

ROFF can't hold negative values, it was designed to support ADCs and DACs with an offset zero. If you have device support that was setting a negative ROFF it was depending on overflowing a uint32 calculation, which gcc allows with the -fwrapv flag but EPICS doesn't set that and it isn't portable.

I don't think we can change this in the record types at all, the device support has to provide any fixes necessary IMHO.