```      SUBROUTINE CLAUU2( UPLO, N, A, LDA, INFO )
*
*  -- LAPACK auxiliary routine (version 3.1) --
*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
*     November 2006
*
*     .. Scalar Arguments ..
CHARACTER          UPLO
INTEGER            INFO, LDA, N
*     ..
*     .. Array Arguments ..
COMPLEX            A( LDA, * )
*     ..
*
*  Purpose
*  =======
*
*  CLAUU2 computes the product U * U' or L' * L, where the triangular
*  factor U or L is stored in the upper or lower triangular part of
*  the array A.
*
*  If UPLO = 'U' or 'u' then the upper triangle of the result is stored,
*  overwriting the factor U in A.
*  If UPLO = 'L' or 'l' then the lower triangle of the result is stored,
*  overwriting the factor L in A.
*
*  This is the unblocked form of the algorithm, calling Level 2 BLAS.
*
*  Arguments
*  =========
*
*  UPLO    (input) CHARACTER*1
*          Specifies whether the triangular factor stored in the array A
*          is upper or lower triangular:
*          = 'U':  Upper triangular
*          = 'L':  Lower triangular
*
*  N       (input) INTEGER
*          The order of the triangular factor U or L.  N >= 0.
*
*  A       (input/output) COMPLEX array, dimension (LDA,N)
*          On entry, the triangular factor U or L.
*          On exit, if UPLO = 'U', the upper triangle of A is
*          overwritten with the upper triangle of the product U * U';
*          if UPLO = 'L', the lower triangle of A is overwritten with
*          the lower triangle of the product L' * L.
*
*  LDA     (input) INTEGER
*          The leading dimension of the array A.  LDA >= max(1,N).
*
*  INFO    (output) INTEGER
*          = 0: successful exit
*          < 0: if INFO = -k, the k-th argument had an illegal value
*
*  =====================================================================
*
*     .. Parameters ..
COMPLEX            ONE
PARAMETER          ( ONE = ( 1.0E+0, 0.0E+0 ) )
*     ..
*     .. Local Scalars ..
LOGICAL            UPPER
INTEGER            I
REAL               AII
*     ..
*     .. External Functions ..
LOGICAL            LSAME
COMPLEX            CDOTC
EXTERNAL           LSAME, CDOTC
*     ..
*     .. External Subroutines ..
EXTERNAL           CGEMV, CLACGV, CSSCAL, XERBLA
*     ..
*     .. Intrinsic Functions ..
INTRINSIC          CMPLX, MAX, REAL
*     ..
*     .. Executable Statements ..
*
*     Test the input parameters.
*
INFO = 0
UPPER = LSAME( UPLO, 'U' )
IF( .NOT.UPPER .AND. .NOT.LSAME( UPLO, 'L' ) ) THEN
INFO = -1
ELSE IF( N.LT.0 ) THEN
INFO = -2
ELSE IF( LDA.LT.MAX( 1, N ) ) THEN
INFO = -4
END IF
IF( INFO.NE.0 ) THEN
CALL XERBLA( 'CLAUU2', -INFO )
RETURN
END IF
*
*     Quick return if possible
*
IF( N.EQ.0 )
\$   RETURN
*
IF( UPPER ) THEN
*
*        Compute the product U * U'.
*
DO 10 I = 1, N
AII = A( I, I )
IF( I.LT.N ) THEN
A( I, I ) = AII*AII + REAL( CDOTC( N-I, A( I, I+1 ), LDA,
\$                     A( I, I+1 ), LDA ) )
CALL CLACGV( N-I, A( I, I+1 ), LDA )
CALL CGEMV( 'No transpose', I-1, N-I, ONE, A( 1, I+1 ),
\$                     LDA, A( I, I+1 ), LDA, CMPLX( AII ),
\$                     A( 1, I ), 1 )
CALL CLACGV( N-I, A( I, I+1 ), LDA )
ELSE
CALL CSSCAL( I, AII, A( 1, I ), 1 )
END IF
10    CONTINUE
*
ELSE
*
*        Compute the product L' * L.
*
DO 20 I = 1, N
AII = A( I, I )
IF( I.LT.N ) THEN
A( I, I ) = AII*AII + REAL( CDOTC( N-I, A( I+1, I ), 1,
\$                     A( I+1, I ), 1 ) )
CALL CLACGV( I-1, A( I, 1 ), LDA )
CALL CGEMV( 'Conjugate transpose', N-I, I-1, ONE,
\$                     A( I+1, 1 ), LDA, A( I+1, I ), 1,
\$                     CMPLX( AII ), A( I, 1 ), LDA )
CALL CLACGV( I-1, A( I, 1 ), LDA )
ELSE
CALL CSSCAL( I, AII, A( I, 1 ), LDA )
END IF
20    CONTINUE
END IF
*
RETURN
*
*     End of CLAUU2
*
END

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