From: "George C. Moschovitis" <gmoscho AT alexander DOT cc DOT ece DOT ntua DOT gr>
Subject: G++ template problem...
To: djgpp AT sun DOT soe DOT clarkson DOT edu (djgpp)
Date: Thu, 13 Jul 1995 16:40:35 +0300 (EET DST)


Hi,

	I was facing some problems with template instantiation under g++ 2.6.3
and thought some one more experienced with the compiler could provide me a so-
lution or workarround... Here comes a little programm that generates the pro-
blem:

----------------------------------------8<----------------------------- v1.h -
// test header //

void	foobar();

template<class T>
class bar {
 T	*p;
 int	k;

 	bar();
       ~bar();

 void	kiki(T a);

 friend	bar2;
};

template<class T>
  bar<T>::bar()
{
  printf("constructor");
}

template<class T>
  bar<T>::~bar()
{
  printf("constructor");
}

template<class T>
  void bar<T>::kiki(T a)
{
  printf("function");
}

class bar2 {
  bar<int>	kuku;
  int   	b;
};


----------------------------------------8<---------------------------- v1.cc -
// test code //

#include <stdio.h>
#include "v1.h"

void foobar()
{
int	a,b;

 b = 3;
 printf("kokokokokoko\n");
 a = b + 2;
 printf("%d",a);
}


i compile with

 gcc -S -c -m486 -O3 t.cc
 

and get the following output:


	.file	"v1.cc"
gcc2_compiled.:
___gnu_compiled_cplusplus:
.text
LC0:
	.ascii "kokokokokoko\12\0"
LC1:
	.ascii "%d\0"
	.align 4
.globl _foobar__Fv
_foobar__Fv:
	pushl %ebp
	movl %esp,%ebp
	pushl $LC0
	call _printf
	pushl $5
	pushl $LC1
	call _printf
	movl %ebp,%esp
	popl %ebp
	ret
LC2:
	.ascii "constructor\0"
	.align 4
.globl ___t3bar1Zi
___t3bar1Zi:
	pushl %ebp
	movl %esp,%ebp
	pushl %ebx
	movl 8(%ebp),%ebx
	pushl $LC2
	call _printf
	movl %ebx,%eax
	movl -4(%ebp),%ebx
	movl %ebp,%esp
	popl %ebp
	ret
	.align 4
.globl __$_t3bar1Zi
__$_t3bar1Zi:
	pushl %ebp
	movl %esp,%ebp
	pushl %esi
	pushl %ebx
	movl 8(%ebp),%esi
	movl 12(%ebp),%ebx
	pushl $LC2
	call _printf
	addl $4,%esp
	testb $1,%bl
	je L33
	pushl %esi
	call ___builtin_delete
L33:
	leal -8(%ebp),%esp
	popl %ebx
	popl %esi
	movl %ebp,%esp
	popl %ebp
	ret
LC3:
	.ascii "function\0"
	.align 4
.globl _kiki__t3bar1Zii
_kiki__t3bar1Zii:
	pushl %ebp
	movl %esp,%ebp
	pushl $LC3
	call _printf
	movl %ebp,%esp
	popl %ebp
	ret


	as u see the code for the constructor/destructor and the test function
of bar is generated even though it is NOT used... I have many .cc files which
i want to compile to a library (.a file)... But they all include a header file
with class definitions and the public ctors/dtors and public functions are ge-
nerated to all of them so i get multiple definition errors when i link my lib-
rary to a programm. Is there any solution to this problem. Btw the other compi-
ler i use (Watcom) doesnt generate multiple definition errors so i guess i am 
not doing something wrong... any help appreciated...


tmL-