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Re: # Re: [RFD] -ffinite-math-only.
Fergus Henderson wrote:
+ Fortran specifies all arithmetic that can result in a NaN or an
+ infinity as "giving undefined results", therefore the compiler
+ by default operates in a way that assumes no NaNs or +-Inf can
+ be generated. If you want to use a NaN or an Inf produced by
+ means other than Fortran, use this option to compile your
+ Fortran program.
This wording seems to imply that Fortran code which produces a NaN or Inf
has undefined behaviour *even if -fno-finite-math-only is specified*.
That's not what I meant, but I can see how you can read it that way.
`Fortran' in the second sentence means `the Fortran language', not the
compiler (i.e., it may include an undefined-behaviour-invoking statement
in your Fortran source, or an assembler or C routine that you call from
your Fortran source).
So, I suggest that the second sentence be changed to this:
If your program might generate or use NaNs or infinities,
then you should use this option.
I agree that this is clearer. I will change it that way.
(Also, "..." should be ``...'' in TexInfo.)
Thanks for the comments.
--
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