--- rpl/lapack/lapack/dlarrb.f	2017/06/17 10:53:56	1.15
+++ rpl/lapack/lapack/dlarrb.f	2023/08/07 08:38:57	1.20
@@ -91,7 +91,7 @@
 *>          RTOL2 is DOUBLE PRECISION
 *>          Tolerance for the convergence of the bisection intervals.
 *>          An interval [LEFT,RIGHT] has converged if
-*>          RIGHT-LEFT.LT.MAX( RTOL1*GAP, RTOL2*MAX(|LEFT|,|RIGHT|) )
+*>          RIGHT-LEFT < MAX( RTOL1*GAP, RTOL2*MAX(|LEFT|,|RIGHT|) )
 *>          where GAP is the (estimated) distance to the nearest
 *>          eigenvalue.
 *> \endverbatim
@@ -107,7 +107,7 @@
 *> \verbatim
 *>          W is DOUBLE PRECISION array, dimension (N)
 *>          On input, W( IFIRST-OFFSET ) through W( ILAST-OFFSET ) are
-*>          estimates of the eigenvalues of L D L^T indexed IFIRST throug
+*>          estimates of the eigenvalues of L D L^T indexed IFIRST through
 *>          ILAST.
 *>          On output, these estimates are refined.
 *> \endverbatim
@@ -117,7 +117,7 @@
 *>          WGAP is DOUBLE PRECISION array, dimension (N-1)
 *>          On input, the (estimated) gaps between consecutive
 *>          eigenvalues of L D L^T, i.e., WGAP(I-OFFSET) is the gap between
-*>          eigenvalues I and I+1. Note that if IFIRST.EQ.ILAST
+*>          eigenvalues I and I+1. Note that if IFIRST = ILAST
 *>          then WGAP(IFIRST-OFFSET) must be set to ZERO.
 *>          On output, these gaps are refined.
 *> \endverbatim
@@ -178,8 +178,6 @@
 *> \author Univ. of Colorado Denver
 *> \author NAG Ltd.
 *
-*> \date December 2016
-*
 *> \ingroup OTHERauxiliary
 *
 *> \par Contributors:
@@ -196,10 +194,9 @@
      $                   RTOL2, OFFSET, W, WGAP, WERR, WORK, IWORK,
      $                   PIVMIN, SPDIAM, TWIST, INFO )
 *
-*  -- LAPACK auxiliary routine (version 3.7.0) --
+*  -- LAPACK auxiliary routine --
 *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
 *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
-*     December 2016
 *
 *     .. Scalar Arguments ..
       INTEGER            IFIRST, ILAST, INFO, N, OFFSET, TWIST
@@ -237,6 +234,12 @@
 *
       INFO = 0
 *
+*     Quick return if possible
+*
+      IF( N.LE.0 ) THEN
+         RETURN
+      END IF
+*
       MAXITR = INT( ( LOG( SPDIAM+PIVMIN )-LOG( PIVMIN ) ) /
      $           LOG( TWO ) ) + 2
       MNWDTH = TWO * PIVMIN