Re: Integer'Size < 32 ?

["W. Wesley Groleau (Wes)" <wwgrol@PSESERV3.FW.HAC.COM>]

There have been many good answers to the two questions about 16 bit
integers (IMHO Dewar's was the clearest) but none of them mentioned
one detail:

One of the queries suggested that constraint_error would be raised
if the compiler did not have a big enough predefined integer type.

The truth is, if such a type is not supported, the compiler is supposed
to refuse to compile the program.

But I have a related question: many of the posts on the topic repeated
the definition

   .... range -(2**31) .. ((2**31)-1)

I once used a compiler for which Integer'Size = 32 and which had an
interesting "feature."  It recognized that the above would fit in 32 bits,
so it compiled for that size.  Then at run-time, it would (obeying
the precedence rules) try to compute 2**31 and raise constraint_error.
(I didn't use the parentheses, but that doesn't change the semantics.)
The ugly work-around was

   .... range  -2**31 .. 2**30 + (2**30 - 1);

My question is, "Is this a common 'feature'?"  (Since so many people have
quoted the same example, I presume the answer is 'no')

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