Allow pointer arithmetic with integer references

Considering these variables:
int i = 3;
int &iref = i;

It's not possible to do any pointer arithmetic with iref:
(gdb) p &i+iref
Argument to arithmetic operation not a number or boolean.

So this adds checks for references to integers in pointer arithmetic.

gdb/ChangeLog:

2020-04-01  Hannes Domani  <ssbssa@yahoo.de>

	PR gdb/24789
	* eval.c (is_integral_or_integral_reference): New function.
	(evaluate_subexp_standard): Allow integer references in
	pointer arithmetic.

gdb/testsuite/ChangeLog:

2020-04-01  Hannes Domani  <ssbssa@yahoo.de>

	PR gdb/24789
	* gdb.cp/misc.cc: Add integer reference variable.
	* gdb.cp/misc.exp: Add test.
This commit is contained in:
Hannes Domani
2020-03-31 14:49:06 +02:00
parent 77bf7b5317
commit 60e22c1eac
5 changed files with 41 additions and 3 deletions

View File

@ -1248,6 +1248,20 @@ skip_undetermined_arglist (int nargs, struct expression *exp, int *pos,
evaluate_subexp (NULL_TYPE, exp, pos, noside);
}
/* Return true if type is integral or reference to integral */
static bool
is_integral_or_integral_reference (struct type *type)
{
if (is_integral_type (type))
return true;
type = check_typedef (type);
return (type != nullptr
&& TYPE_IS_REFERENCE (type)
&& is_integral_type (TYPE_TARGET_TYPE (type)));
}
struct value *
evaluate_subexp_standard (struct type *expect_type,
struct expression *exp, int *pos,
@ -2208,10 +2222,10 @@ evaluate_subexp_standard (struct type *expect_type,
if (binop_user_defined_p (op, arg1, arg2))
return value_x_binop (arg1, arg2, op, OP_NULL, noside);
else if (ptrmath_type_p (exp->language_defn, value_type (arg1))
&& is_integral_type (value_type (arg2)))
&& is_integral_or_integral_reference (value_type (arg2)))
return value_ptradd (arg1, value_as_long (arg2));
else if (ptrmath_type_p (exp->language_defn, value_type (arg2))
&& is_integral_type (value_type (arg1)))
&& is_integral_or_integral_reference (value_type (arg1)))
return value_ptradd (arg2, value_as_long (arg1));
else
{
@ -2234,7 +2248,7 @@ evaluate_subexp_standard (struct type *expect_type,
return value_from_longest (type, value_ptrdiff (arg1, arg2));
}
else if (ptrmath_type_p (exp->language_defn, value_type (arg1))
&& is_integral_type (value_type (arg2)))
&& is_integral_or_integral_reference (value_type (arg2)))
return value_ptradd (arg1, - value_as_long (arg2));
else
{