bug#36370: 27.0.50; XFIXNAT called on negative numbers

[Paul Eggert]

Bruno Haible wrote:

> I like this wording.

OK, I merged that into the wording I proposed and installed the attached. One 
new point that I added is that I sometimes use 'assume (X)' to pacify GCC so 
that it does not issue a bogus warning in nearby code; this benefit of 'assume' 
is independent of the efficiency of the generated code.

0001-verify-document-assume-better.txt
Description: Text document