This is with the polyhedron test gas_dyn.f90 http://www.polyhedron.co.uk/pb05/polyhedron_benchmark_suite.html
It only occurs for gas_dyn.f90 and only with -m32 (-m64 is ok). This is with gcc-Version 4.3.0 20070621 on x86_64-unknown-linux-gnu. gfortran -m32 -march=opteron -ftree-vectorize -O1 gas_dyn.f90 time ./a.out real 0m0.005s -- Summary: [4.3 Regression] Complete program optimized away (i686, -ftree-vectorize) Product: gcc Version: 4.3.0 Status: UNCONFIRMED Keywords: wrong-code Severity: major Priority: P3 Component: target AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: burnus at gcc dot gnu dot org GCC target triplet: i586-unknown-linux-gnu http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32457