[rfa/Ada] Remove builtin types from type/value printing routines

["Ulrich Weigand" <uweigand@de.ibm.com>]

Hello Joel,

the remaining references to global integer builtin types are all related
to type/value printing.  Various places that are unable to determine a
proper type to use for printing integer values fall back to a default
builtin_type_int32 type.

The precise properties of this type do not actually matter, however;
it only serves as means to indicate to ada_print_scalar to print the
value as a default signed integer.

This patch simply changes ada_print_scalar to accept a NULL type
argument to indicate the same thing, and updates the callers to
use NULL instead of builtin_type_int32.

(A non-obvious instance of this is ada_variant_discrim_type, which
returns a type that is solely used as argument to ada_print_scalar,
after having been passed through print_choices.) 

Tested on amd64-linux.  OK for mainline?

Bye,
Ulrich


ChangeLog:

	* ada-valprint.c (ada_print_scalar): Accept NULL type argument
	to indicate scalar should be printed as default integer.
	(print_optional_low_bound): Pass NULL to ada_print_scalar to
	indicate default integer output.
	* ada-typeprint.c (print_range, print_range_bound): Likewise.
	(print_choices): Likewise.  Thus, accept NULL as val_type.
	* ada-lang.c (ada_variant_discrim_type): Return NULL when failed
	to look up controlling discriminant name.


Index: gdb-head/gdb/ada-lang.c
===================================================================
--- gdb-head.orig/gdb/ada-lang.c
+++ gdb-head/gdb/ada-lang.c
@@ -5645,18 +5645,14 @@ ada_is_variant_part (struct type *type, 
 
 /* Assuming that VAR_TYPE is a variant wrapper (type of the variant part)
    whose discriminants are contained in the record type OUTER_TYPE,
-   returns the type of the controlling discriminant for the variant.  */
+   returns the type of the controlling discriminant for the variant.
+   May return NULL if the type could not be found.  */
 
 struct type *
 ada_variant_discrim_type (struct type *var_type, struct type *outer_type)
 {
   char *name = ada_variant_discrim_name (var_type);
-  struct type *type =
-    ada_lookup_struct_elt_type (outer_type, name, 1, 1, NULL);
-  if (type == NULL)
-    return builtin_type_int32;
-  else
-    return type;
+  return ada_lookup_struct_elt_type (outer_type, name, 1, 1, NULL);
 }
 
 /* Assuming that TYPE is the type of a variant wrapper, and FIELD_NUM is a
Index: gdb-head/gdb/ada-typeprint.c
===================================================================
--- gdb-head.orig/gdb/ada-typeprint.c
+++ gdb-head/gdb/ada-typeprint.c
@@ -133,7 +133,7 @@ print_range (struct type *type, struct u
     case TYPE_CODE_ENUM:
       break;
     default:
-      target_type = builtin_type_int32;
+      target_type = NULL;
       break;
     }
 
@@ -181,12 +181,12 @@ print_range_bound (struct type *type, ch
          be printed as a signed or an unsigned value.  This causes
          the upper bound of the 0 .. -1 range types to be printed as
          a very large unsigned number instead of -1.
-         To workaround this stabs deficiency, we replace the TYPE by
-         builtin_type_int32 when we detect that the bound is negative,
+         To workaround this stabs deficiency, we replace the TYPE by NULL
+         to indicate default output when we detect that the bound is negative,
          and the type is a TYPE_CODE_INT.  The bound is negative when
          'm' is the last character of the number scanned in BOUNDS.  */
       if (bounds[*n - 1] == 'm' && TYPE_CODE (type) == TYPE_CODE_INT)
-	type = builtin_type_int32;
+	type = NULL;
       ada_print_scalar (type, B, stream);
       if (bounds[*n] == '_')
 	*n += 2;
@@ -423,7 +423,7 @@ print_array_type (struct type *type, str
 }
 
 /* Print the choices encoded by field FIELD_NUM of variant-part TYPE on
-   STREAM, assuming the VAL_TYPE is the type of the values.  */
+   STREAM, assuming that VAL_TYPE (if non-NULL) is the type of the values.  */
 
 static void
 print_choices (struct type *type, int field_num, struct ui_file *stream,
Index: gdb-head/gdb/ada-valprint.c
===================================================================
--- gdb-head.orig/gdb/ada-valprint.c
+++ gdb-head/gdb/ada-valprint.c
@@ -122,7 +122,7 @@ print_optional_low_bound (struct ui_file
 	return 0;
       break;
     case TYPE_CODE_UNDEF:
-      index_type = builtin_type_int32;
+      index_type = NULL;
       /* FALL THROUGH */
     default:
       if (low_bound == 1)
@@ -375,7 +375,8 @@ ada_printchar (int c, struct type *type,
 }
 
 /* [From print_type_scalar in typeprint.c].   Print VAL on STREAM in a
-   form appropriate for TYPE.  */
+   form appropriate for TYPE, if non-NULL.  If TYPE is NULL, print VAL
+   like a default signed integer.  */
 
 void
 ada_print_scalar (struct type *type, LONGEST val, struct ui_file *stream)
@@ -383,6 +384,12 @@ ada_print_scalar (struct type *type, LON
   unsigned int i;
   unsigned len;
 
+  if (!type)
+    {
+      print_longest (stream, 'd', 0, val);
+      return;
+    }
+
   type = ada_check_typedef (type);
 
   switch (TYPE_CODE (type))
-- 
  Dr. Ulrich Weigand
  GNU Toolchain for Linux on System z and Cell BE
  Ulrich.Weigand@de.ibm.com