[Bug tree-optimization/86101] New: [8/9 Regression] IEEE_UNDERFLOW_FLAG in 416.gamess with -Ofast -march=native on bdver4

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86101

            Bug ID: 86101
           Summary: [8/9 Regression] IEEE_UNDERFLOW_FLAG in 416.gamess
                    with -Ofast -march=native on bdver4
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: marxin at gcc dot gnu.org
                CC: rguenth at gcc dot gnu.org
            Blocks: 26163
  Target Milestone: ---

Starting from r259592 the benchmark fails:

****************************************
Contents of h2ocu2+.gradient.err
****************************************
Note: The following floating-point exceptions are signalling:
IEEE_UNDERFLOW_FLAG

****************************************

****************************************
Contents of triazolium.err
****************************************
Note: The following floating-point exceptions are signalling: IEEE_INVALID_FLAG

****************************************

*** Miscompare of cytosine.2.out; for details see
   
/home/gcc/buildworker/source/cpu2006/benchspec/CPU2006/416.gamess/run/run_peak_ref_amd64-m64-mine.0001/cytosine.2.out.mis

Flags:
-Ofast -march=native -g -std=legacy


Referenced Bugs:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=26163
[Bug 26163] [meta-bug] missed optimization in SPEC (2k17, 2k and 2k6 and 95)