https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80158
--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> --- SUBROUTINE DRPAUL(SMAT,TMAT,EPS,EPT,SIJ,TIJ,WRK,VEC,ARRAY,FMO, * XMKVIR,TMJ,XMI,YMI,ZMI,ZQQ,L1,L1EF,LNA,LNA2, * NAEF,L2,NLOC,NVIR,PROVEC,FOCKMA,MXBF,MXMO2) DIMENSION CMO(L1,L1),TLOC(LNA,LNA),SMJ(L1,NAEF),XMK(L1,LNA) DO I = 1,LNA DO J = 1,LNA IF (I.LE.NOUT) TLOC(I,J) = ZERO IF (J.LE.NOUT) TLOC(I,J) = ZERO END DO DO NA=1,NOC IF ( ABS(E(NI)-E(NA)) .GE.TOL) THEN END IF END DO END DO END possibly somewhat nonsensical reduced but it reproduces the issue.