[Bug fortran/31139] sum(w_re(1:nn,1)*fi(i(1:nn, ii))) up to 3.5x slower than C version

[pinskia at gcc dot gnu dot org]

------- Comment #3 from pinskia at gcc dot gnu dot org  2007-03-12 05:33 -------
The problem here is obvious, in the Fortran case, there is a temp array being
created while in the C case, there is not.  Also in the optimized C case, the
multiplication of the complex numbers is incorrect unless you add -ffast-math. 
Actually I think in both C cases it is incorrect.  Can someone try with
-ffast-math for both the C and Fortran cases?


complex * complex is not a simple cross product in FP world.


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31139