From ccccdb8d9b339972382604e17d0e451fa590f1a0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tobias=20Schl=C3=BCter?=
 <tobias.schlueter@physik.uni-muenchen.de>
Date: Wed, 6 Apr 2005 20:03:09 +0200
Subject: [PATCH] expr.c (gfc_check_assign): Don't allow NULL as rhs in a
 non-pointer assignment.

fortran/
* expr.c (gfc_check_assign): Don't allow NULL as rhs in a
non-pointer assignment.

testsuite/
* gfortran.dg/pr15754.f90: Change annotations to dg-error.

From-SVN: r97740
---
 gcc/fortran/ChangeLog                 |  5 +++++
 gcc/fortran/expr.c                    | 11 ++++++-----
 gcc/testsuite/ChangeLog               |  4 ++++
 gcc/testsuite/gfortran.dg/pr15754.f90 |  4 ++--
 4 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/gcc/fortran/ChangeLog b/gcc/fortran/ChangeLog
index fed9ec3d271..990eb18c289 100644
--- a/gcc/fortran/ChangeLog
+++ b/gcc/fortran/ChangeLog
@@ -1,3 +1,8 @@
+2005-04-06  Tobias Schl"uter  <tobias.schlueter@physik.uni-muenchen.de>
+
+	* expr.c (gfc_check_assign): Don't allow NULL as rhs in a
+	non-pointer assignment.
+
 2005-04-05  Feng Wang  <fengwang@nudt.edu.cn>
 
 	PR fortran/15959
diff --git a/gcc/fortran/expr.c b/gcc/fortran/expr.c
index f4a4b589b1f..d0c99e335a0 100644
--- a/gcc/fortran/expr.c
+++ b/gcc/fortran/expr.c
@@ -1789,11 +1789,12 @@ gfc_check_assign (gfc_expr * lvalue, gfc_expr * rvalue, int conform)
       return FAILURE;
     }
 
-  /* This is a guaranteed segfault and possibly a typo: p = NULL()
-     instead of p => NULL()  */
-  if (rvalue->expr_type == EXPR_NULL)
-    gfc_warning ("NULL appears on right-hand side in assignment at %L",
-		 &rvalue->where);
+   if (rvalue->expr_type == EXPR_NULL)
+     {
+       gfc_error ("NULL appears on right-hand side in assignment at %L",
+		  &rvalue->where);
+       return FAILURE;
+     }
 
   /* This is possibly a typo: x = f() instead of x => f()  */
   if (gfc_option.warn_surprising 
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 962e7e0059d..dc98fcd7d63 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2005-04-06  Tobias Schl"uter  <tobias.schlueter@physik.uni-muenchen.de>
+
+	* gfortran.dg/pr15754.f90: Change annotations to dg-error.
+
 2005-04-06  Joseph S. Myers  <joseph@codesourcery.com>
 
 	* gcc.dg/weak/weak-12.c, g++.dg/ext/weak2.C: New tests.
diff --git a/gcc/testsuite/gfortran.dg/pr15754.f90 b/gcc/testsuite/gfortran.dg/pr15754.f90
index 6d8e34f28db..f595d6e2ac6 100644
--- a/gcc/testsuite/gfortran.dg/pr15754.f90
+++ b/gcc/testsuite/gfortran.dg/pr15754.f90
@@ -1,7 +1,7 @@
 ! we didn't give a warning if the RHS of an assignment was NULL
 ! { dg-do-compile }
 INTEGER, POINTER :: P
-I = NULL() ! { dg-warning "NULL appears" "Assignment non-pointer = NULL" }
-P = NULL() ! { dg-warning "NULL appears" "Assignment pointer = NULL" }
+I = NULL() ! { dg-error "NULL appears" "Assignment non-pointer = NULL" }
+P = NULL() ! { dg-error "NULL appears" "Assignment pointer = NULL" }
 P => NULL()
 END