🚀 go-pugleaf

It seems that G++ 1.34.1 may not always correctly disambiguate
method references when the & (address-of) operator is used.
It looks like this can result in incorrect code generation
as demonstrated below.

What follows is a short example source file followed by the
code generated for it (on a Sun3)  by G++ 1.34.1.  It appears
that the code generated for the final assignment to "vp"
within the function called "test" is incorrect.


--------------------------------------------------------------------
// Check that it is legal to take the address of an overloaded
// operator as long as the context of the & operator requires
// that a specific (unambigous) type of pointer-to-function
// with arguments be yielded by the &.

// #include "Testinc.h"

overload function;

void function (char c)
{
	c = c;
}

void function (float f)
{
	f = f;
}

class base {
public:
	void method (char);
	void method (float);
};

void* vp;

typedef void (*ptr_to_func_of_char)(char);
typedef void (*ptr_to_func_of_float)(float);
typedef void (base::*ptr_to_method_of_char)(char);
typedef void (base::*ptr_to_method_of_float)(float);

int test ()
{
	vp = (ptr_to_func_of_char) &function;
	vp = (ptr_to_func_of_float) &function;
	vp = (ptr_to_method_of_char) &base::method;
	vp = (ptr_to_method_of_float) &base::method;	// bad code?
	return 0;
}

void base::method (char c)
{
	c = c;
}

void base::method (float f)
{
	f = f;
}
----------------------------------------------------------------------
#NO_APP
gcc_compiled.:
.text
	.even
.globl _function_QI
_function_QI:
	link a6,#0
	moveb a6@(11),a6@(11)
L1:
	unlk a6
	rts
	.even
.globl _function_SF
_function_SF:
	link a6,#0
L2:
	unlk a6
	rts
	.even
.globl _test
_test:
	link a6,#0
	movel #_function_QI,_vp
	movel #_function_SF,_vp
	movel #_method_PSbase_QI,_vp
	movel #_method_PSbase_QI,_vp		; should be #_method_PSbase_SF
	clrl d1
	movel d1,d0
	jra L3
L3:
	unlk a6
	rts
	.even
.globl _method_PSbase_QI
_method_PSbase_QI:
	link a6,#0
	moveb a6@(15),a6@(15)
L4:
	unlk a6
	rts
	.even
.globl _method_PSbase_SF
_method_PSbase_SF:
	link a6,#0
L5:
	unlk a6
	rts
.comm _vp,4
----------------------------------------------------------------------------

// Ron Guilmette  -  MCC  -  Experimental Systems Kit Project
// 3500 West Balcones Center Drive,  Austin, TX  78759  -  (512)338-3740
// ARPA: rfg@mcc.com
// UUCP: {rutgers,uunet,gatech,ames,pyramid}!cs.utexas.edu!pp!rfg