[PATCH]: include types in invalid operand error messages

["Daniel Berlin" <dberlin at dberlin dot org>]

This patch changes our error messages for dereferencing and binary
operators to include the types involved, which is much friendlier to
the user.

For:
int main(void)
{
 struct foostruct
   {
     int a;
   } foo;
 int t, *q;
 t + foo;
 *t;
}

We used to print:
t.c: In function 'main':
t.c:8: error: invalid operands to binary +
t.c:9: error: invalid type argument of 'unary *'

With this patch, we print:
t.c:8: error: invalid operands to binary + (have 'int' and 'struct foostruct')
t.c:9: error: invalid type argument of 'unary *' (have 'int')


Because our regexps still match in the testsuite, this does not cause
any testsuite failures.

Bootstrapped and regtested on i686-darwin
Okay for mainline?

in gcc/

2007-05-31  Daniel Berlin  <dberlin@dberlin.org>

       * c-typeck.c (build_indirect_ref): Include type in error message.
       (build_binary_op): Pass types to binary_op_error.
       * c-common.c (binary_op_error): Take two type arguments, print out
       types with error.
       * c-common.h (binary_op_error): Update prototype.

in gcc/cp

2007-05-31  Daniel Berlin  <dberlin@dberlin.org>

       * typeck.c (build_binary_op): Include types in error.
Index: cp/typeck.c
===================================================================
--- cp/typeck.c	(revision 125030)
+++ cp/typeck.c	(working copy)
@@ -3552,7 +3552,7 @@ build_binary_op (enum tree_code code, tr
 	      || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
 							TREE_TYPE (type1)))
 	    {
-	      binary_op_error (code);
+	      binary_op_error (code, type0, type1);
 	      return error_mark_node;
 	    }
 	  arithmetic_types_p = 1;
Index: c-typeck.c
===================================================================
--- c-typeck.c	(revision 125030)
+++ c-typeck.c	(working copy)
@@ -1923,7 +1923,7 @@ build_indirect_ref (tree ptr, const char
 	}
     }
   else if (TREE_CODE (pointer) != ERROR_MARK)
-    error ("invalid type argument of %qs", errorstring);
+    error ("invalid type argument of %qs (have %qT)", errorstring, type);
   return error_mark_node;
 }
 
@@ -8135,7 +8135,7 @@ build_binary_op (enum tree_code code, tr
 	  || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
 						    TREE_TYPE (type1))))
     {
-      binary_op_error (code);
+      binary_op_error (code, type0, type1);
       return error_mark_node;
     }
 
@@ -8435,7 +8435,7 @@ build_binary_op (enum tree_code code, tr
 
   if (!result_type)
     {
-      binary_op_error (code);
+      binary_op_error (code, TREE_TYPE (op0), TREE_TYPE (op1));
       return error_mark_node;
     }
 
Index: c-common.c
===================================================================
--- c-common.c	(revision 125030)
+++ c-common.c	(working copy)
@@ -2230,10 +2230,10 @@ min_precision (tree value, int unsignedp
 }
 
 /* Print an error message for invalid operands to arith operation
-   CODE.  */
+   CODE with TYPE0 for operand 0, and TYPE1 for operand 1.  */
 
 void
-binary_op_error (enum tree_code code)
+binary_op_error (enum tree_code code, tree type0, tree type1)
 {
   const char *opname;
 
@@ -2284,7 +2284,8 @@ binary_op_error (enum tree_code code)
     default:
       gcc_unreachable ();
     }
-  error ("invalid operands to binary %s", opname);
+  error ("invalid operands to binary %s (have %qT and %qT)", opname,
+	 type0, type1);
 }
 
 /* Subroutine of build_binary_op, used for comparison operations.
Index: c-common.h
===================================================================
--- c-common.h	(revision 125030)
+++ c-common.h	(working copy)
@@ -677,7 +677,7 @@ extern tree c_sizeof_or_alignof_type (tr
 extern tree c_alignof_expr (tree);
 /* Print an error message for invalid operands to arith operation CODE.
    NOP_EXPR is used as a special case (see truthvalue_conversion).  */
-extern void binary_op_error (enum tree_code);
+extern void binary_op_error (enum tree_code, tree, tree);
 extern tree fix_string_type (tree);
 struct varray_head_tag;
 extern void constant_expression_warning (tree);