[Bug middle-end/42558] New: [4.5 Regression] miscompilation related to -floop-block

[jv244 at cam dot ac dot uk]

The attached testcase miscompiles as:

> gfortran -floop-block    -O2  -funroll-loops -ffast-math bug.f90
> ./a.out
   4.0000000000000000

> gfortran   -O2  -funroll-loops -ffast-math bug.f90
> ./a.out
   1.0000000000000000

> gfortran bug.f90> ./a.out
   1.0000000000000000

4.4 works fine, 4.5 miscompiles


-- 
           Summary: [4.5 Regression] miscompilation related to -floop-block
           Product: gcc
           Version: 4.5.0
            Status: UNCONFIRMED
          Keywords: wrong-code
          Severity: normal
          Priority: P3
         Component: middle-end
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: jv244 at cam dot ac dot uk


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42558