------- Comment #119 from jv244 at cam dot ac dot uk 2007-06-27 08:24 ------- Testing gcc 4.2.0 I unfortunately found that it miscompiles CP2K.
The following testcase: tests/DFTB/regtest-scc/h2o-1.inp yields incorrect results. Should be similar to: Total energy: -130.561836 whereas one gets Total energy: -127.642599 This is a very large difference beyond numerics. The miscompilation is triggered by: # BUG FCFLAGS = -O3 -ffast-math -ftree-vectorize -march=native but not # OK FCFLAGS = -O3 -ffast-math -march=native # OK FCFLAGS = -O3 -funroll-loops -ftree-vectorize -march=native I might try to find out which module gets miscompiled, but this could be a bit of a slow process. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29975
