[gfortran] patch for PR 14396 - Intrinsic SQRT and CSQRT givewrong answer with COMPLEX argument.

[Bud Davis <bdavis9659 at comcast dot net>]

sqrt and csqrt are using a local instead of the passed in parameter.

note that if you do not use the gfortran version of these routines you
will not see the problem.

Here is the bugzilla link with some info on which platforms can
duplicate it and which cannot.

 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14396 



No additional testsuite regressions.  Tested i686/gnu/linux.


Here is a test case that fails before and passes after the patch is installed:

C PR 14396
C extracted from intrinsic77.f in the g77 testsuite
      logical fail
      common /flags/ fail
      fail = .false.
      call square_root
      if (fail) call abort
      end
      subroutine square_root
      intrinsic sqrt, dsqrt, csqrt
      real x, a
      x = 4.0
      a = 2.0
      call c_r(SQRT(x),a,'SQRT(real)')
      call c_d(SQRT(1.d0*x),1.d0*a,'SQRT(double)')
      call c_c(SQRT((1.,0.)*x),(1.,0.)*a,'SQRT(complex)')
      call c_d(DSQRT(1.d0*x),1.d0*a,'DSQRT(double)')
      call c_c(CSQRT((1.,0.)*x),(1.,0.)*a,'CSQRT(complex)')
      call p_r_r(SQRT,x,a,'SQRT')
      call p_d_d(DSQRT,1.d0*x,1.d0*a,'DSQRT')
      call p_c_c(CSQRT,(1.,0.)*x,(1.,0.)*a ,'CSQRT')
      end
      subroutine failure(label)
c     Report failure and set flag
      character*(*) label
      logical fail
      common /flags/ fail
      write(6,'(a,a,a)') 'Test ',label,' FAILED'
      fail = .true.
      end
      subroutine c_r(a,b,label)
c     Check if REAL a equals b, and fail otherwise
      real a, b
      character*(*) label
      if ( abs(a-b) .gt. 1.0e-5 ) then
         call failure(label)
         write(6,*) 'Got ',a,' expected ', b
      end if
      end
      subroutine c_d(a,b,label)
c     Check if DOUBLE PRECISION a equals b, and fail otherwise
      double precision a, b
      character*(*) label
      if ( abs(a-b) .gt. 1.0d-5 ) then
         call failure(label)
         write(6,*) 'Got ',a,' expected ', b
      end if
      end
 
      subroutine c_c(a,b,label)
c     Check if COMPLEX a equals b, and fail otherwise
      complex a, b
      character*(*) label
      if ( abs(a-b) .gt. 1.0e-5 ) then
         call failure(label)
         write(6,*) 'Got ',a,' expected ', b
      end if
      end
      subroutine p_r_r(f,x,a,label)
c     Check if REAL f(x) equals a for REAL x
      real f,x,a
      character*(*) label
      call c_r(f(x),a,label)
      end
      subroutine p_d_d(f,x,a,label)
c     Check if DOUBLE PRECISION f(x) equals a for DOUBLE PRECISION x
      double precision f,x,a
      character*(*) label
      call c_d(f(x),a,label)
      end
      subroutine p_c_c(f,x,a,label)
c     Check if COMPLEX f(x) equals a for COMPLEX x
      complex f,x,a
      character*(*) label
      call c_c(f(x),a,label)
      end


2004-03-06	Bud Davis	<bdavis9659@comcast.net>

	PR 14396
	* generated/exp_c4.c(csqrtf)
        * generated/exp_c8.c(csqrt): Use parameter as input.

    
regards,
bud  

    

Index: gcc/libgfortran/generated/exp_c4.c
===================================================================
RCS file: /cvs/gcc/gcc/libgfortran/generated/Attic/exp_c4.c,v
retrieving revision 1.1.2.3
diff -c -3 -p -r1.1.2.3 exp_c4.c
*** gcc/libgfortran/generated/exp_c4.c  19 Sep 2003 19:11:11 -0000      1.1.2.3
--- gcc/libgfortran/generated/exp_c4.c  6 Mar 2004 15:37:15 -0000
*************** csqrtf (GFC_COMPLEX_4 z)
*** 92,99 ****
    GFC_REAL_4 im;
    GFC_COMPLEX_4 v;
   
!   re = REALPART (re);
!   im = IMAGPART (im);
    if (im == 0.0)
      {
        if (re < 0.0)
--- 92,99 ----
    GFC_REAL_4 im;
    GFC_COMPLEX_4 v;
   
!   re = REALPART (z);
!   im = IMAGPART (z);
    if (im == 0.0)
      {
        if (re < 0.0)
Index: gcc/libgfortran/generated/exp_c8.c
===================================================================
RCS file: /cvs/gcc/gcc/libgfortran/generated/Attic/exp_c8.c,v
retrieving revision 1.1.2.3
diff -c -3 -p -r1.1.2.3 exp_c8.c
*** gcc/libgfortran/generated/exp_c8.c  19 Sep 2003 19:11:11 -0000      1.1.2.3
--- gcc/libgfortran/generated/exp_c8.c  6 Mar 2004 15:37:15 -0000
*************** csqrt (GFC_COMPLEX_8 z)
*** 92,99 ****
    GFC_REAL_8 im;
    GFC_COMPLEX_8 v;
   
!   re = REALPART (re);
!   im = IMAGPART (im);
    if (im == 0.0)
      {
        if (re < 0.0)
--- 92,99 ----
    GFC_REAL_8 im;
    GFC_COMPLEX_8 v;
   
!   re = REALPART (z);
!   im = IMAGPART (z);
    if (im == 0.0)
      {
        if (re < 0.0)