On the assigned file you can reproduce the bug. If you compile this file with -O2 the error occures, only way is use -O0 or use volatile statement for the double arrays.
I think this should be checkt during optimization. Greets, Matthias -- Summary: Register not cleand correctly by acessing thru pointer Product: gcc Version: 4.3.4 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: matthias at goldhoorn dot eu GCC build triplet: amd64 GCC host triplet: amd64 GCC target triplet: amd64 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43401