[Bug fortran/52053] SUM intrinsic is wrong for very large arrays

[dominiq at lps dot ens.fr]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52053

--- Comment #1 from Dominique d'Humieres <dominiq at lps dot ens.fr> 2012-01-30 14:28:13 UTC ---
This is not a bug: 16777216. == 2.0**24, then you can add 1.0 as much as you
like without changing the result.

If one want a bug here, it is a missed optimization as SUM does not seem to be
vectorized (one day I should compile libgfortran with -O3 and the option
allowing operations to be reordered).