Robert Dewar wrote:
FX Coudert wrote:
In Fortran, integers are used to index arrays. So if you want
integer overflow checking, use -fbounds-check :-)
I know there is a smiley here, but it seems to me that range checking
is quite different from overflow checking.
I think what Toon was alluding to is that "real" Fortran programmers
don't use integers except for array subscripts. Real life is floating-
point based!
Well as a one-time real Fortran programmer i would say that comes
under the rubric of common misconception. Sure there are lots of
fpt operations in Fortran code, but probably most Fortran programs
have more integer arithmetic operations than fpt operations, and
by no means all are about array indexing :-)
I can't remember if Knuth's empirical study of actual Fortran
code commented on this situation (that was the study that showed
that the average expression in Fortran has only a few terms,
unfortunately it is not available unless you pay $30 :-) on the web.
Well, the solution of the question: "Does Fortran require the catching
of signed integer overflow" certainly needs the resolution of the
question: Does Fortran (the language) require to specify the extent of
integers.
Well, it doesn't (it is a implementation quality issue). So the issue
really becomes: when is integer overflow a quality of implementation
issue ? If you can't index arrays with them - therefore, my remark.
--
Toon Moene - e-mail: [EMAIL PROTECTED] - phone: +31 346 214290
Saturnushof 14, 3738 XG Maartensdijk, The Netherlands
At home: http://moene.indiv.nluug.nl/~toon/
Progress of GNU Fortran: http://gcc.gnu.org/ml/gcc/2008-01/msg00009.html
