Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!MCC.COM!rfg
From: rfg@MCC.COM (Ron Guilmette)
Newsgroups: gnu.g++.bug
Subject: BUG in G++ 1.35.0- (pre-release)
Message-ID: <8905022253.AA17731@riunite.aca.mcc.com>
Date: 2 May 89 22:53:59 GMT
Sender: daemon@tut.cis.ohio-state.edu
Distribution: gnu
Organization: GNUs Not Usenet
Lines: 75


As the following short program demonstrates, G++ 1.35.0- breaks
the semantics of the method-call operator ->()() in that it causes
the method call operator to be invoked *even* when it didn't use to
be, i.e. when you are calling a member function of the current
class from within another member function of the current class.

The following patch seems to fix the problem, but I am not at all sure
that this is the "correct" solution.  It just seems to work.

diff -rc2 1.35-.0--/cplus-class.c 1.35-.0-+/cplus-class.c
*** 1.35-.0--/cplus-class.c	Wed Apr 19 00:45:12 1989
--- 1.35-.0-+/cplus-class.c	Tue May  2 17:31:14 1989
***************
*** 3454,3458 ****
  	       || strncmp (IDENTIFIER_POINTER (DECL_NAME (function)),
  			   "op$method_call", 13))
! 	   && (may_be_remote (basetype) || instance != C_C_D))
      {
        register int used, size;
--- 3454,3458 ----
  	       || strncmp (IDENTIFIER_POINTER (DECL_NAME (function)),
  			   "op$method_call", 13))
! 	   && (may_be_remote (basetype) || (C_C_D ? (TREE_TYPE (instance) != TREE_TYPE(C_C_D)) : 1 )))
      {
        register int used, size;

---------------------------------------------------------------------------------
typedef int MP;

class base;

typedef void (base::*base_method_ptr) ();

class base {
	int member;
public:
	base () {}
	base operator ->() (MP method_id, int arg_bytes, ...)
	{
		base_method_ptr bmp = (base_method_ptr) method_id;

		printf ("operator->()() called\n");
		(this->*(bmp)) ();
	}
};

class derived : public base {
	int member;
public:
	derived () {}
	void method_1 ()
	{
		printf ("method_1() called\n");
	}
	void method_2 ()
	{
		printf ("method_2() called\n");
		method_1 ();
	}
};

int main ()
{
	derived derived_object;

	derived_object.method_2 ();
}
---------------------------------------------------------------------------------


// Ron Guilmette  -  MCC  -  Experimental Systems Kit Project
// 3500 West Balcones Center Drive,  Austin, TX  78759  -  (512)338-3740
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