From fb4e77d379b20fa00dff4614d42ad1089490cdfd Mon Sep 17 00:00:00 2001
From: Martin Kroeker <martin@ruby.chemie.uni-freiburg.de>
Date: Wed, 24 Jun 2026 13:27:17 +0200
Subject: [PATCH] Query correct (larger) workspace for VL=N,VR=V
 (Reference-LAPACK PR 1274)

---
 lapack-netlib/SRC/sggev3.f | 48 +++++++++++++++++++++++++-------------
 1 file changed, 32 insertions(+), 16 deletions(-)

diff --git a/lapack-netlib/SRC/sggev3.f b/lapack-netlib/SRC/sggev3.f
index d788d11472..9fbe6bafef 100644
--- a/lapack-netlib/SRC/sggev3.f
+++ b/lapack-netlib/SRC/sggev3.f
@@ -5,7 +5,6 @@
 * Online html documentation available at
 *            http://www.netlib.org/lapack/explore-html/
 *
-*> \htmlonly
 *> Download SGGEV3 + dependencies
 *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/sggev3.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/sggev3.f">
 *> [TXT]</a>
-*> \endhtmlonly
 *
 *  Definition:
 *  ===========
@@ -225,6 +223,7 @@
       SUBROUTINE SGGEV3( JOBVL, JOBVR, N, A, LDA, B, LDB, ALPHAR,
      $                   ALPHAI, BETA, VL, LDVL, VR, LDVR, WORK, LWORK,
      $                   INFO )
+      IMPLICIT NONE
 *
 *  -- LAPACK driver routine --
 *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
@@ -259,13 +258,16 @@ SUBROUTINE SGGEV3( JOBVL, JOBVR, N, A, LDA, B, LDB, ALPHAR,
       LOGICAL            LDUMMA( 1 )
 *     ..
 *     .. External Subroutines ..
-      EXTERNAL           SGEQRF, SGGBAK, SGGBAL, SGGHD3, SLAQZ0, SLACPY,
-     $                   SLASCL, SLASET, SORGQR, SORMQR, STGEVC
+      EXTERNAL           SGEQRF, SGGBAK, SGGBAL,
+     $                   SGGHD3, SLAQZ0, SLACPY,
+     $                   SLASCL, SLASET, SORGQR,
+     $                   SORMQR, STGEVC
 *     ..
 *     .. External Functions ..
       LOGICAL            LSAME
       REAL               SLAMCH, SLANGE, SROUNDUP_LWORK
-      EXTERNAL           LSAME, SLAMCH, SLANGE, SROUNDUP_LWORK
+      EXTERNAL           LSAME, SLAMCH, SLANGE,
+     $                   SROUNDUP_LWORK
 *     ..
 *     .. Intrinsic Functions ..
       INTRINSIC          ABS, MAX, SQRT
@@ -327,18 +329,23 @@ SUBROUTINE SGGEV3( JOBVL, JOBVR, N, A, LDA, B, LDB, ALPHAR,
          LWKOPT = MAX( LWKMIN, 3*N+INT( WORK( 1 ) ) )
          CALL SORMQR( 'L', 'T', N, N, N, B, LDB, WORK, A, LDA, WORK,
      $                -1, IERR )
-         LWKOPT = MAX( LWKOPT, 3*N+INT( WORK( 1 ) ) )
-         CALL SGGHD3( JOBVL, JOBVR, N, 1, N, A, LDA, B, LDB, VL, LDVL,
-     $                VR, LDVR, WORK, -1, IERR )
          LWKOPT = MAX( LWKOPT, 3*N+INT( WORK( 1 ) ) )
          IF( ILVL ) THEN
             CALL SORGQR( N, N, N, VL, LDVL, WORK, WORK, -1, IERR )
             LWKOPT = MAX( LWKOPT, 3*N+INT( WORK( 1 ) ) )
+         END IF
+         IF( ILV ) THEN
+            CALL SGGHD3( JOBVL, JOBVR, N, 1, N, A, LDA, B, LDB, VL,
+     $                   LDVL, VR, LDVR, WORK, -1, IERR )
+            LWKOPT = MAX( LWKOPT, 3*N+INT( WORK( 1 ) ) )
             CALL SLAQZ0( 'S', JOBVL, JOBVR, N, 1, N, A, LDA, B, LDB,
      $                   ALPHAR, ALPHAI, BETA, VL, LDVL, VR, LDVR,
      $                   WORK, -1, 0, IERR )
             LWKOPT = MAX( LWKOPT, 2*N+INT( WORK( 1 ) ) )
          ELSE
+            CALL SGGHD3( 'N', 'N', N, 1, N, A, LDA, B, LDB, VL, LDVL,
+     $                   VR, LDVR, WORK, -1, IERR )
+            LWKOPT = MAX( LWKOPT, 3*N+INT( WORK( 1 ) ) )
             CALL SLAQZ0( 'E', JOBVL, JOBVR, N, 1, N, A, LDA, B, LDB,
      $                   ALPHAR, ALPHAI, BETA, VL, LDVL, VR, LDVR,
      $                   WORK, -1, 0, IERR )
@@ -431,7 +438,8 @@ SUBROUTINE SGGEV3( JOBVL, JOBVR, N, A, LDA, B, LDB, ALPHAR,
       IF( ILVL ) THEN
          CALL SLASET( 'Full', N, N, ZERO, ONE, VL, LDVL )
          IF( IROWS.GT.1 ) THEN
-            CALL SLACPY( 'L', IROWS-1, IROWS-1, B( ILO+1, ILO ), LDB,
+            CALL SLACPY( 'L', IROWS-1, IROWS-1,
+     $                   B( ILO+1, ILO ), LDB,
      $                   VL( ILO+1, ILO ), LDVL )
          END IF
          CALL SORGQR( IROWS, IROWS, IROWS, VL( ILO, ILO ), LDVL,
@@ -449,11 +457,16 @@ SUBROUTINE SGGEV3( JOBVL, JOBVR, N, A, LDA, B, LDB, ALPHAR,
 *
 *        Eigenvectors requested -- work on whole matrix.
 *
-         CALL SGGHD3( JOBVL, JOBVR, N, ILO, IHI, A, LDA, B, LDB, VL,
-     $                LDVL, VR, LDVR, WORK( IWRK ), LWORK+1-IWRK, IERR )
+         CALL SGGHD3( JOBVL, JOBVR, N, ILO, IHI,
+     $                A, LDA,
+     $                B, LDB, VL,
+     $                LDVL, VR, LDVR,
+     $                WORK( IWRK ), LWORK+1-IWRK, IERR )
       ELSE
-         CALL SGGHD3( 'N', 'N', IROWS, 1, IROWS, A( ILO, ILO ), LDA,
-     $                B( ILO, ILO ), LDB, VL, LDVL, VR, LDVR,
+         CALL SGGHD3( 'N', 'N', IROWS, 1, IROWS,
+     $                A( ILO, ILO ), LDA,
+     $                B( ILO, ILO ), LDB, VL,
+     $                LDVL, VR, LDVR,
      $                WORK( IWRK ), LWORK+1-IWRK, IERR )
       END IF
 *
@@ -492,7 +505,8 @@ SUBROUTINE SGGEV3( JOBVL, JOBVR, N, A, LDA, B, LDB, ALPHAR,
          ELSE
             CHTEMP = 'R'
          END IF
-         CALL STGEVC( CHTEMP, 'B', LDUMMA, N, A, LDA, B, LDB, VL, LDVL,
+         CALL STGEVC( CHTEMP, 'B', LDUMMA, N, A, LDA, B, LDB, VL,
+     $                LDVL,
      $                VR, LDVR, N, IN, WORK( IWRK ), IERR )
          IF( IERR.NE.0 ) THEN
             INFO = N + 2
@@ -575,8 +589,10 @@ SUBROUTINE SGGEV3( JOBVL, JOBVR, N, A, LDA, B, LDB, ALPHAR,
   110 CONTINUE
 *
       IF( ILASCL ) THEN
-         CALL SLASCL( 'G', 0, 0, ANRMTO, ANRM, N, 1, ALPHAR, N, IERR )
-         CALL SLASCL( 'G', 0, 0, ANRMTO, ANRM, N, 1, ALPHAI, N, IERR )
+         CALL SLASCL( 'G', 0, 0, ANRMTO, ANRM, N, 1, ALPHAR, N,
+     $                IERR )
+         CALL SLASCL( 'G', 0, 0, ANRMTO, ANRM, N, 1, ALPHAI, N,
+     $                IERR )
       END IF
 *
       IF( ILBSCL ) THEN