[Bug libfortran/49336] ATAN2 values differ from those specified in documentation

["kargl at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49336

kargl at gcc dot gnu.org changed:

           What    |Removed                     |Added
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                 CC|                            |kargl at gcc dot gnu.org

--- Comment #1 from kargl at gcc dot gnu.org 2011-06-09 02:44:07 UTC ---
The documentation is correct for a Fortran 95 compiler.  Try
adding -std=f95 to your command line.

gfortran implements most of the Fortran 2003 and some Fortran
2008 features.  With F2003, one finds in Sec. 1.6.1.

   If the processor can distinguish between positive and negative
   real zero, this standard requires different returned values for
   ATAN2(Y,X) when X < 0 and Y is negative real zero and for LOG(X)
   and SQRT(X) when X is complex with REAL(X) < 0 and negative zero
   imaginary part.

If you want to be hero, you are more than welcomed to submit a 
patch.  F2003 says the results are

   If Y = 0 and X > 0, the result is Y.  If Y = 0 and X < 0, then
   the result is pi if Y is positive real zero or the processor
   cannot distinguish between positive and negative real zero, and
   âpi if Y is negative real zero.