[rfa] handle integer downsizing correctly in C++ overloading

[David Carlton <carlton@math.stanford.edu>]

GDB currently won't let you do narrowing integer conversions when
calling an overloaded C++ function: compile this,

int overloadChar(char c)
{
  return 29;
}

int main()
{
  overloadChar(1);
}

break on main, and try to print overloadChar(1).

The problem is that gdbtypes.h defines both INTEGER_COERCION_BADNESS
and INTEGER_CONVERSION_BADNESS.  The former is unacceptably bad; the
latter isn't preferred, but isn't acceptable.  And in all (or almost
all) cases, the type comparison functions use INTEGER_COERCION_BADNESS
when doing narrowing integer comparisons, when they should use
INTEGER_CONVERSION_BADNESS.

In fact, INTEGER_COERCION_BADNESS shouldn't exist: there's no such
thing as an unacceptably bad integer conversion.  So this patch
changes all uses of INTEGER_COERCION_BADNESS to refer to
INTEGER_CONVERSION_BADNESS, deletes INTEGER_COERCION_BADNESS, and also
deletes FLOAT_COERCION_BADNESS (which is similarly unnecessary but
which is already correctly unused).  And there's a testsuite patch
included to catch this as well.

Tested on i686-pc-linux-gnu/GCC3.1/DWARF-2; OK to commit?

David Carlton
carlton@math.stanford.edu

2003-01-31  David Carlton  <carlton@math.stanford.edu>

	* gdbtypes.h: Delete INTEGER_COERCION_BADNESS,
	FLOAT_COERCION_BADNESS.
	* gdbtypes.c (rank_one_type): Replace all uses of
	INTEGER_COERCION_BADNESS by INTEGER_CONVERSION_BADNESS.

2003-01-31  David Carlton  <carlton@math.stanford.edu>

	* gdb.c++/overload.exp: Test intToChar(1).
	* gdb.c++/overload.cc (intToChar): New.
	(main): Call intToChar.

Index: gdbtypes.h
===================================================================
RCS file: /cvs/src/src/gdb/gdbtypes.h,v
retrieving revision 1.42
diff -u -p -r1.42 gdbtypes.h
--- gdbtypes.h	19 Jan 2003 04:06:45 -0000	1.42
+++ gdbtypes.h	31 Jan 2003 19:26:04 -0000
@@ -1211,10 +1211,6 @@ extern int count_virtual_fns (struct typ
 #define TOO_FEW_PARAMS_BADNESS       100
 /* Badness if no conversion among types */
 #define INCOMPATIBLE_TYPE_BADNESS    100
-/* Badness of coercing large integer to smaller size */
-#define INTEGER_COERCION_BADNESS     100
-/* Badness of coercing large floating type to smaller size */
-#define FLOAT_COERCION_BADNESS       100
 
 /* Badness of integral promotion */
 #define INTEGER_PROMOTION_BADNESS      1
Index: gdbtypes.c
===================================================================
RCS file: /cvs/src/src/gdb/gdbtypes.c,v
retrieving revision 1.69
diff -u -p -r1.69 gdbtypes.c
--- gdbtypes.c	17 Jan 2003 19:12:18 -0000	1.69
+++ gdbtypes.c	31 Jan 2003 19:28:36 -0000
@@ -2591,7 +2591,7 @@ rank_one_type (struct type *parm, struct
 		  if (TYPE_NOSIGN (arg))	/* plain char -> plain char */
 		    return 0;
 		  else
-		    return INTEGER_COERCION_BADNESS;	/* signed/unsigned char -> plain char */
+		    return INTEGER_CONVERSION_BADNESS;	/* signed/unsigned char -> plain char */
 		}
 	      else if (TYPE_UNSIGNED (parm))
 		{
@@ -2604,13 +2604,13 @@ rank_one_type (struct type *parm, struct
 			       && integer_types_same_name_p (TYPE_NAME (parm), "long"))
 			return INTEGER_PROMOTION_BADNESS;	/* unsigned int -> unsigned long */
 		      else
-			return INTEGER_COERCION_BADNESS;	/* unsigned long -> unsigned int */
+			return INTEGER_CONVERSION_BADNESS;	/* unsigned long -> unsigned int */
 		    }
 		  else
 		    {
 		      if (integer_types_same_name_p (TYPE_NAME (arg), "long")
 			  && integer_types_same_name_p (TYPE_NAME (parm), "int"))
-			return INTEGER_COERCION_BADNESS;	/* signed long -> unsigned int */
+			return INTEGER_CONVERSION_BADNESS;	/* signed long -> unsigned int */
 		      else
 			return INTEGER_CONVERSION_BADNESS;	/* signed int/long -> unsigned int/long */
 		    }
@@ -2623,15 +2623,15 @@ rank_one_type (struct type *parm, struct
 			   && integer_types_same_name_p (TYPE_NAME (parm), "long"))
 		    return INTEGER_PROMOTION_BADNESS;
 		  else
-		    return INTEGER_COERCION_BADNESS;
+		    return INTEGER_CONVERSION_BADNESS;
 		}
 	      else
-		return INTEGER_COERCION_BADNESS;
+		return INTEGER_CONVERSION_BADNESS;
 	    }
 	  else if (TYPE_LENGTH (arg) < TYPE_LENGTH (parm))
 	    return INTEGER_PROMOTION_BADNESS;
 	  else
-	    return INTEGER_COERCION_BADNESS;
+	    return INTEGER_CONVERSION_BADNESS;
 	case TYPE_CODE_ENUM:
 	case TYPE_CODE_CHAR:
 	case TYPE_CODE_RANGE:
@@ -2653,7 +2653,7 @@ rank_one_type (struct type *parm, struct
 	case TYPE_CODE_RANGE:
 	case TYPE_CODE_BOOL:
 	case TYPE_CODE_ENUM:
-	  return INTEGER_COERCION_BADNESS;
+	  return INTEGER_CONVERSION_BADNESS;
 	case TYPE_CODE_FLT:
 	  return INT_FLOAT_CONVERSION_BADNESS;
 	default:
@@ -2666,12 +2666,12 @@ rank_one_type (struct type *parm, struct
 	case TYPE_CODE_RANGE:
 	case TYPE_CODE_BOOL:
 	case TYPE_CODE_ENUM:
-	  return INTEGER_COERCION_BADNESS;
+	  return INTEGER_CONVERSION_BADNESS;
 	case TYPE_CODE_FLT:
 	  return INT_FLOAT_CONVERSION_BADNESS;
 	case TYPE_CODE_INT:
 	  if (TYPE_LENGTH (arg) > TYPE_LENGTH (parm))
-	    return INTEGER_COERCION_BADNESS;
+	    return INTEGER_CONVERSION_BADNESS;
 	  else if (TYPE_LENGTH (arg) < TYPE_LENGTH (parm))
 	    return INTEGER_PROMOTION_BADNESS;
 	  /* >>> !! else fall through !! <<< */
@@ -2683,7 +2683,7 @@ rank_one_type (struct type *parm, struct
 	      if (TYPE_NOSIGN (arg))
 		return 0;
 	      else
-		return INTEGER_COERCION_BADNESS;
+		return INTEGER_CONVERSION_BADNESS;
 	    }
 	  else if (TYPE_UNSIGNED (parm))
 	    {
@@ -2695,7 +2695,7 @@ rank_one_type (struct type *parm, struct
 	  else if (!TYPE_NOSIGN (arg) && !TYPE_UNSIGNED (arg))
 	    return 0;
 	  else
-	    return INTEGER_COERCION_BADNESS;
+	    return INTEGER_CONVERSION_BADNESS;
 	default:
 	  return INCOMPATIBLE_TYPE_BADNESS;
 	}
@@ -2708,7 +2708,7 @@ rank_one_type (struct type *parm, struct
 	case TYPE_CODE_RANGE:
 	case TYPE_CODE_BOOL:
 	case TYPE_CODE_ENUM:
-	  return INTEGER_COERCION_BADNESS;
+	  return INTEGER_CONVERSION_BADNESS;
 	case TYPE_CODE_FLT:
 	  return INT_FLOAT_CONVERSION_BADNESS;
 	default: