Support casting capabilities/capability pointers to other types

When casting capabilities and capability pointers to other types, we truncate
the value to the appropriate size, given some capabilities are greater than
8 bytes in size.

gdb/ChangeLog:

2020-11-11  Luis Machado  <luis.machado@arm.com>

	* valops.c (value_cast): Handle casting from capabilities and
	capability pointers.

diff --git a/gdb/valops.c b/gdb/valops.c
index d4e89a3cfa6840ef4988f53cd36f930c40025fd9..d1fe6d1024d359ef52f3e80e113b9d625cafd4aa 100644 (file)
--- a/gdb/valops.c
+++ b/gdb/valops.c
@@ -529,14 +529,20 @@ value_cast (struct type *type, struct value *arg2)
            || code2 == TYPE_CODE_RANGE
            || is_fixed_point_type (type2));
 
-  /* Handle casting capabilities to other scalar types.  For now we truncate
-     the capability value to the size of the target type.  */
-  if (scalar && code2 == TYPE_CODE_CAPABILITY)
+  int to_scalar = (code1 == TYPE_CODE_INT || code1 == TYPE_CODE_FLT
+           || code1 == TYPE_CODE_DECFLOAT || code1 == TYPE_CODE_ENUM
+           || code1 == TYPE_CODE_RANGE);
+
+  /* Handle casting capabilities/capability pointers to other scalar types.
+     For now we truncate the capability value to the size of the target
+     type.  */
+  if (to_scalar && (code2 == TYPE_CODE_CAPABILITY
+      || (code2 == TYPE_CODE_PTR && TYPE_CAPABILITY (type2))))
     {
       if (type->is_unsigned ())
-       value_from_ulongest (to_type, value_as_long (arg2));
+       return value_from_ulongest (to_type, value_as_long (arg2));
       else
-       value_from_longest (to_type, value_as_long (arg2));
+       return value_from_longest (to_type, value_as_long (arg2));
     }
 
   if ((code1 == TYPE_CODE_STRUCT || code1 == TYPE_CODE_UNION)