Re: [PATCH] Objective-C language support.

Michael Snyder
2002-10-08T23:42:54Z

Adam Fedor wrote:
>
> This patch adds Objective-C language support to gdb based upon a patch
> provided by Apple Computer Inc from their version of gdb. Note that the
> patch only contains changes to existing files. New files (objc-lang.h,
> objc-lang.c, objc-exp.y) and a gdb.objc testsuite directory are located at
>
> ftp://ftp.gnustep.org/pub/gnustep/contrib/gdb-objc-patch.tar.gz

Adam, this bit can't hurt anything, since it just adds some new enum
values. Only one suggestion -- how about putting OP_THIS and OP_SELF
consecutively, because they're so similar? Also please hold off on
the export of evaluate_subexp -- let's handle that separately.

Other than that, approved. Wait a couple days for objections, then
you can commit it.

> * expression.h: New ops NSSTRING, SELECTOR, MSGCALL, and SELF.

> Index: gdb/expression.h
> ===================================================================
> RCS file: /cvs/src/src/gdb/expression.h,v
> retrieving revision 1.4
> diff -u -p -r1.4 expression.h
> --- gdb/expression.h 1 Aug 2002 17:18:32 -0000 1.4
> +++ gdb/expression.h 17 Sep 2002 19:30:05 -0000
> @@ -181,6 +181,12 @@ enum exp_opcode
> making three exp_elements. */
> OP_FUNCALL,
>
> + /* OP_MSGCALL is followed by a string in the next exp_element and then an
> + integer. The string is the selector string. The integer is the number
> + of arguments to the message call. That many plus one values are used,
> + the first one being the object pointer. This is an Objective C message */
> + OP_MSGCALL,
> +
> /* This is EXACTLY like OP_FUNCALL but is semantically different.
> In F77, array subscript expressions, substring expressions
> and function calls are all exactly the same syntactically. They may
> @@ -273,11 +279,17 @@ enum exp_opcode
> STRUCTOP_STRUCT,
> STRUCTOP_PTR,
>
> - /* C++ */
> - /* OP_THIS is just a placeholder for the class instance variable.
> + /* C++: OP_THIS is just a placeholder for the class instance variable.
> It just comes in a tight (OP_THIS, OP_THIS) pair. */
> OP_THIS,
>
> + /* Objective C: "@selector" pseudo-operator */
> + OP_SELECTOR,
> +
> + /* Objective-C: OP_SELF is just a placeholder for the class instance
> + variable. It just comes in a tight (OP_SELF, OP_SELF) pair. */
> + OP_SELF,
> +
> /* OP_SCOPE surrounds a type name and a field name. The type
> name is encoded as one element, but the field name stays as
> a string, which, of course, is variable length. */
> @@ -305,7 +317,10 @@ enum exp_opcode
> OP_NAME,
>
> /* An unparsed expression. Used for Scheme (for now at least) */
> - OP_EXPRSTRING
> + OP_EXPRSTRING,
> +
> + /* An Objective C Foundation Class NSString constant */
> + OP_NSSTRING,
> };
>
> union exp_element
> @@ -369,6 +384,10 @@ enum noside
>
> extern struct value *evaluate_subexp_standard
> (struct type *, struct expression *, int *, enum noside);
> +
> +extern struct value *evaluate_subexp (struct type *, struct expression *,
> + int *, enum noside);
> +
>
> /* From expprint.c */
>