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 A problem with pointers to member functions ?

 g++ 1.36.2- + patches posted in gnu.g++.bug ( also fails with 1.36.0 )
 Running on a convex-c1 (convex unix 7.1), collect2 is used for loading.

 tm.h@ -> ./config/tm-convex1.h
 md@ -> ./config/convex.md

 This code is derived from the squares demo in Interviews, there appears to 
 be problem with pointers to member functions when vtbls are used.
 
 If the code is compiled with -Dvtbl ( which forces the class to have a
 virtual function table ) it fails, see below.

 This code works fine ether way on a sun4 and a DECstation3100.
  

Script started on Wed Dec  6 14:18:33 1989

hanauma 301> cat testdn.c

#include <stream.h>

class SquaresFrame;

typedef void (SquaresFrame::*MenuFunc)();

class SquaresFrame  {
public:
	SquaresFrame();
	void DoCommands( MenuFunc[], int );

	void Print1();
#ifdef vtbl	
	virtual void Print2();
#else
	void Print2();
#endif
};


SquaresFrame::SquaresFrame () { }

void SquaresFrame::DoCommands( MenuFunc funcs[], int num ) {
    for (int i = 0; i <num ; i++) {
	 ( this->*funcs[i])();
    }
}

void SquaresFrame::Print1() { cout << "1 \n" ; }
void SquaresFrame::Print2() { cout << "2 \n" ; }



main() {

MenuFunc funclist[2] = {  &SquaresFrame::Print1 , &SquaresFrame::Print2 };

SquaresFrame* test= new SquaresFrame();

test->DoCommands(funclist,2);

}

****** The SquaresFrame class doesn't have a vtbl in this case  ********

hanauma 302> g++ -v -g -I/usr/local/include/g++-include testdn.c
g++ version 1.36.2- (based on GCC 1.36)
 /usr/local/lib/gcc-cpp -+ -v -I/usr/local/include/g++-include -undef -D__GNUC__ -D__GNUG__ -D__cplusplus -Dconvex -Dparsec -Dunix -D__convex__ -D__parsec__ -D__unix__ testdn.c /usr/tmp/cc023439.cpp
GNU CPP version 1.36
 /usr/local/lib/gcc-cc1plus /usr/tmp/cc023439.cpp -quiet -dumpbase testdn.c -g -version -o /usr/tmp/cc023439.s
GNU C++ version 1.36.2- (based on GCC 1.36) (convex) compiled by GNU C version 1.36.
default target switches: -mc1
 as -o testdn.o /usr/tmp/cc023439.s
 /usr/local/lib/gcc-ld /lib/crt0.o testdn.o -lg++ /usr/local/lib/gcc-gnulib -lg -lc
hanauma 303> a.out
1 
2 


****** now force the SquaresFrame class to have a vtbl  ********

hanauma 304> g++ -v -g -I/usr/local/include/g++-include testdn.c -Dvtbl
g++ version 1.36.2- (based on GCC 1.36)
 /usr/local/lib/gcc-cpp -+ -v -Dvtbl -I/usr/local/include/g++-include -undef -D__GNUC__ -D__GNUG__ -D__cplusplus -Dconvex -Dparsec -Dunix -D__convex__ -D__parsec__ -D__unix__ testdn.c /usr/tmp/cc023488.cpp
GNU CPP version 1.36
 /usr/local/lib/gcc-cc1plus /usr/tmp/cc023488.cpp -quiet -dumpbase testdn.c -g -version -o /usr/tmp/cc023488.s
GNU C++ version 1.36.2- (based on GCC 1.36) (convex) compiled by GNU C version 1.36.
default target switches: -mc1
 as -o testdn.o /usr/tmp/cc023488.s
 /usr/local/lib/gcc-ld /lib/crt0.o testdn.o -lg++ /usr/local/lib/gcc-gnulib -lg -lc

hanauma 305> a.out
Segmentation fault (core dumped)

hanauma 306> gdb a.out
GDB 3.4, Copyright (C) 1989 Free Software Foundation, Inc.
There is ABSOLUTELY NO WARRANTY for GDB; type "info warranty" for details.
GDB is free software and you are welcome to distribute copies of it
 under certain conditions; type "info copying" to see the conditions.
Reading symbol data from /sep/dave/test/g++/a.out...done.
Type "help" for a list of commands.
(gdb) run
Starting program: /sep/dave/test/g++/a.out 

Program received signal 11, Segmentation fault
0x80000000 in gen$soff ()
(gdb) where
#0  0x80000000 in gen$soff ()
#1  0x80001260 in DoCommands__12SquaresFramePPM12SquaresFrameFv_vi (...) (...)
#2  0x800013f2 in main (...) (...)
(gdb) up
Reading in symbols for testdn.c...done.
#1  0x80001260 in DoCommands__12SquaresFramePPM12SquaresFrameFv_vi ($this=(SquaresFrame *) 0x80019000, funcs=(MenuFunc *) 0xffffcda8, num=2) (testdn.c line 26)
26		 ( this->*funcs[i])();
(gdb) p funcs[0]
$1 = (MenuFunc) (MenuFunc) 268436047
(gdb) q
The program is running.  Quit anyway? (y or n) y


Notes
-----

(1) gdb on the convex never seems to print out the member functions nicely 
like it does on a sun4, this may or may not be related.

(2) If only one function is present (remove all references to print1 ) it
works fine.