Eric R posted (from the PoP):
<snip>
When, during the generation of the address, an
address is obtained that exceeds the value allowed
for the address size (2^24 - 1, 2^31 - 1, or 2^64 - 1), one of
the following two actions is taken:

1. The carry out of the high-order bit position of the
address is ignored. This handling of an address
of excessive size is called wraparound.

2. An interruption condition is recognized.

...

Addresses generated by the CPU that may be virtual
addresses always wrap.
</snip>

That post omitted this phrase from the PoP that follows shortly after:

For CPU table entries that are addressed by real or absolute addresses, it 
is unpredictable
whether the address wraps or an addressing exception is recognized.

Paul G wrote:
<snip>
An interrupt condition is *never* recognized "during generation of [an] 
address." 
</snip>

Therefore we conclude that this statement is not correct for the case of 
CPU table entries addressed by real or absolute addresses.
(I don't know exactly what a "CPU table entry" is in this context.)

Peter Relson
z/OS Core Technology Design


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