Enable .XOR. operator with -std=legacy.

	gcc/fortran/
	* match.c (gfc_match_intrinsic_op): Match ".XOR." with -std=legacy.
	* gfortran.texi: Document.

	gcc/testsuite/gfortran.dg/
	* dec_logical_xor_1.f90: New.
        * dec_logical_xor_2.f90: New.
        * dec_logical_xor_3.f03: New.

From-SVN: r241520

gcc/fortran/ChangeLog

 2016-10-25  Fritz Reese <fritzoreese@gmail.com>
 
+	* match.c (gfc_match_intrinsic_op): Match ".XOR." with -std=legacy.
+	* gfortran.texi: Document.
+
+2016-10-25  Fritz Reese <fritzoreese@gmail.com>
+
 	* primary.c (gfc_match_rvalue): Match %LOC as LOC with -std=legacy.
 	* gfortran.texi: Document.
 

gcc/fortran/gfortran.texi

@@ -1468,6 +1468,7 @@ compatibility extensions along with those enabled by @option{-std=legacy}.
 * Form feed as whitespace::
 * TYPE as an alias for PRINT::
 * %LOC as an rvalue::
+* .XOR. operator::
 @end menu
 
 @node Old-style kind specifications
@@ -2558,6 +2559,14 @@ integer :: i
 call sub(%loc(i))
 @end smallexample
 
+@node .XOR. operator
+@subsection .XOR. operator
+@cindex operators, xor
+
+GNU Fortran supports @code{.XOR.} as a logical operator with @code{-std=legacy}
+for compatibility with legacy code. @code{.XOR.} is equivalent to
+@code{.NEQV.}. That is, the output is true if and only if the inputs differ.
+
 
 @node Extensions not implemented in GNU Fortran
 @section Extensions not implemented in GNU Fortran
@@ -2582,7 +2591,6 @@ code that uses them running with the GNU Fortran compiler.
 * Variable FORMAT expressions::
 @c * Q edit descriptor::
 @c * TYPE and ACCEPT I/O Statements::
-@c * .XOR. operator::
 @c * CARRIAGECONTROL, DEFAULTFILE, DISPOSE and RECORDTYPE I/O specifiers::
 @c * Omitted arguments in procedure call::
 * Alternate complex function syntax::

gcc/fortran/match.c

@@ -960,6 +960,19 @@ gfc_match_intrinsic_op (gfc_intrinsic_op *result)
 	    }
 	  break;
 
+	case 'x':
+	  if (gfc_next_ascii_char () == 'o'
+	      && gfc_next_ascii_char () == 'r'
+	      && gfc_next_ascii_char () == '.')
+	    {
+              if (!gfc_notify_std (GFC_STD_LEGACY, ".XOR. operator at %C"))
+                return MATCH_ERROR;
+	      /* Matched ".xor." - equivalent to ".neqv.".  */
+	      *result = INTRINSIC_NEQV;
+	      return MATCH_YES;
+	    }
+	  break;
+
 	default:
 	  break;
 	}

gcc/testsuite/ChangeLog

 2016-10-25  Fritz Reese <fritzoreese@gmail.com>
 
+	* gfortran.dg/dec_logical_xor_1.f90: New test.
+	* gfortran.dg/dec_logical_xor_2.f90: New test.
+	* gfortran.dg/dec_logical_xor_3.f03: New test.
+
+2016-10-25  Fritz Reese <fritzoreese@gmail.com>
+
 	* gfortran.dg/dec_loc_rval_1.f90: New test.
 	* gfortran.dg/dec_loc_rval_2.f90: New test.
-	* gfortran.dg/dec_loc_rval_3.f90: New test.
+	* gfortran.dg/dec_loc_rval_3.f03: New test.
 
 2016-10-25  Fritz Reese <fritzoreese@gmail.com>
 

gcc/testsuite/gfortran.dg/dec_logical_xor_1.f90

+! { dg-do run }
+! { dg-options "-std=legacy" }
+!
+! Test logical .XOR. operator.
+!
+
+implicit none
+
+logical :: in1, in2, neqv_out, lxor_out, truth_table(2)
+integer :: i, j, ixor_out, ieor_out
+
+truth_table(1) = .true.
+truth_table(2) = .false.
+do i = 1,2
+  do j = 1,2
+    in1 = truth_table(j)
+    in2 = truth_table(i)
+
+    ! make sure logical xor works
+    neqv_out = in1 .neqv. in2
+    lxor_out = in1 .xor. in2
+
+    if ( neqv_out .neqv. lxor_out ) then
+      print *, "(",in1,in2,") .neqv.: ",neqv_out,"  .xor.: ",lxor_out
+      call abort()
+    endif
+
+    ! make sure we didn't break xor() intrinsic
+    ixor_out = xor(i*7, j*5)
+    ieor_out = ieor(i*7, j*5)
+
+    if ( ixor_out .ne. ieor_out ) then
+      print *, "(",in1,in2,") ieor(): ",ieor_out,"  xor(): ",ixor_out
+      call abort()
+    endif
+
+  enddo
+enddo
+
+end

gcc/testsuite/gfortran.dg/dec_logical_xor_2.f90

+! { dg-do compile }
+! { dg-options "-std=gnu" }
+!
+! Test warnings for logical .XOR. operator without -std=legacy.
+!
+
+implicit none
+
+logical, volatile :: in1, in2, xor_out
+xor_out = in1 .xor. in2 ! { dg-warning ".XOR. operator" }
+
+end

gcc/testsuite/gfortran.dg/dec_logical_xor_3.f03

+! { dg-do compile }
+! { dg-options "-std=f2003" }
+!
+! Test errors for logical .XOR. operator with a real standard.
+!
+
+implicit none
+
+logical, volatile :: in1, in2, xor_out
+xor_out = in1 .xor. in2 ! { dg-error ".XOR. operator" }
+
+end