Integer Range Question

[Mendal@SU-SIERRA.ARPA (Geoff Mendal)]

Here's another brain twister from the hackers at Stanford.
We're trying to determine whether the following predefined
integer type is valid (assume that it is the only predefined
integer type):

  type Integer is range 1 .. 0;

The real question here is whether a null range is "symmetric about
zero", as required for all predefined integer types.  Also at
issue is whether System.Min_Int *must* be negative, and likewise
System.Max_Int positive.

We don't know the answer, so any help is appreciated.

LRM references: 3.5(3); 3.5.4(6..7,13); 13.7.1(2..3)

gom
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