bug#32605: 26.1; (random) never returns negative

[Francis Wright]

According to my reading of both the documentation for the function
random and its description in the manual, if it is called with no
argument then "the value might be any integer representable in Lisp,
i.e., an integer between ‘most-negative-fixnum’ and
‘most-positive-fixnum’".  Therefore, it should return a negative integer
half the time, but I have never yet seen it return a negative value.  So
either the documentation or the implementation is wrong.  For what it's
worth, I would prefer the documented behaviour over the current actual
behaviour.


In GNU Emacs 26.1 (build 1, x86_64-w64-mingw32)
 of 2018-05-30 built on CIRROCUMULUS
Repository revision: 07f8f9bc5a51f5aa94eb099f3e15fbe0c20ea1ea
Windowing system distributor 'Microsoft Corp.', version 10.0.17134
Recent messages:
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Saving file c:/Users/fjw/REDUCE@SourceForge/emacs/REDUCE/Big Integer 
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