From faa10e60e4dac3d6951aee758c41bcafd7885e54 Mon Sep 17 00:00:00 2001
From: Martin Kroeker <martin@ruby.chemie.uni-freiburg.de>
Date: Wed, 24 Jun 2026 21:34:29 +0200
Subject: [PATCH] Fix scaling of relative error to avoid spurious failures
 (Reference-LAPACK PR 1309)

---
 lapack-netlib/SRC/dlarrf.f | 7 +++----
 lapack-netlib/SRC/slarrf.f | 7 +++----
 2 files changed, 6 insertions(+), 8 deletions(-)

diff --git a/lapack-netlib/SRC/dlarrf.f b/lapack-netlib/SRC/dlarrf.f
index a496e1b2d8..9b6fe329bc 100644
--- a/lapack-netlib/SRC/dlarrf.f
+++ b/lapack-netlib/SRC/dlarrf.f
@@ -5,7 +5,6 @@
 * Online html documentation available at
 *            http://www.netlib.org/lapack/explore-html/
 *
-*> \htmlonly
 *> Download DLARRF + dependencies
 *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dlarrf.f">
 *> [TGZ]</a>
@@ -13,7 +12,6 @@
 *> [ZIP]</a>
 *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dlarrf.f">
 *> [TXT]</a>
-*> \endhtmlonly
 *
 *  Definition:
 *  ===========
@@ -174,7 +172,7 @@
 *> \author Univ. of Colorado Denver
 *> \author NAG Ltd.
 *
-*> \ingroup OTHERauxiliary
+*> \ingroup larrf
 *
 *> \par Contributors:
 *  ==================
@@ -190,6 +188,7 @@ SUBROUTINE DLARRF( N, D, L, LD, CLSTRT, CLEND,
      $                   W, WGAP, WERR,
      $                   SPDIAM, CLGAPL, CLGAPR, PIVMIN, SIGMA,
      $                   DPLUS, LPLUS, WORK, INFO )
+      IMPLICIT NONE
 *
 *  -- LAPACK auxiliary routine --
 *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
@@ -466,7 +465,7 @@ SUBROUTINE DLARRF( N, D, L, LD, CLSTRT, CLEND,
       ELSE
 *        None of the representations investigated satisfied our
 *        criteria. Take the best one we found.
-         IF((SMLGROWTH.LT.FAIL).OR.NOFAIL) THEN
+         IF((SMLGROWTH.LT.FAIL*SPDIAM).OR.NOFAIL) THEN
             LSIGMA = BESTSHIFT
             RSIGMA = BESTSHIFT
             FORCER = .TRUE.
diff --git a/lapack-netlib/SRC/slarrf.f b/lapack-netlib/SRC/slarrf.f
index 3a6bea32d5..7eeae0a381 100644
--- a/lapack-netlib/SRC/slarrf.f
+++ b/lapack-netlib/SRC/slarrf.f
@@ -5,7 +5,6 @@
 * Online html documentation available at
 *            http://www.netlib.org/lapack/explore-html/
 *
-*> \htmlonly
 *> Download SLARRF + dependencies
 *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/slarrf.f">
 *> [TGZ]</a>
@@ -13,7 +12,6 @@
 *> [ZIP]</a>
 *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/slarrf.f">
 *> [TXT]</a>
-*> \endhtmlonly
 *
 *  Definition:
 *  ===========
@@ -174,7 +172,7 @@
 *> \author Univ. of Colorado Denver
 *> \author NAG Ltd.
 *
-*> \ingroup OTHERauxiliary
+*> \ingroup larrf
 *
 *> \par Contributors:
 *  ==================
@@ -190,6 +188,7 @@ SUBROUTINE SLARRF( N, D, L, LD, CLSTRT, CLEND,
      $                   W, WGAP, WERR,
      $                   SPDIAM, CLGAPL, CLGAPR, PIVMIN, SIGMA,
      $                   DPLUS, LPLUS, WORK, INFO )
+      IMPLICIT NONE
 *
 *  -- LAPACK auxiliary routine --
 *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
@@ -466,7 +465,7 @@ SUBROUTINE SLARRF( N, D, L, LD, CLSTRT, CLEND,
       ELSE
 *        None of the representations investigated satisfied our
 *        criteria. Take the best one we found.
-         IF((SMLGROWTH.LT.FAIL).OR.NOFAIL) THEN
+         IF((SMLGROWTH.LT.FAIL*SPDIAM).OR.NOFAIL) THEN
             LSIGMA = BESTSHIFT
             RSIGMA = BESTSHIFT
             FORCER = .TRUE.