Undefined reference to template function ...

[Her, Il]

Yes, it is compiled well with gcc 3.4.6,
but it doesn't work with gcc 4.1.2


thank you

Her, Il
Technology Consulting
Technology Service Korea

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il.her@hp.com

-----Original Message-----
From: Ian Lance Taylor [mailto:iant@google.com] 
Sent: Tuesday, May 31, 2011 10:51 PM
To: Her, Il
Cc: gcc-help@gcc.gnu.org
Subject: Re: Undefined reference to template function ...

"Her, Il" <il.her@hp.com> writes:

> Thank you for answering my question.
> Here is my sample.
>
> [Test.h]
> #ifndef __TEST_hh
> #define __TEST_hh
> struct TEST
> {
> 	int a, b;
> };
> #endif
>
> [sub.h]
> #include <stdio.h>
> template <typename T> struct Base
> {
> 	void dump(T &r);
> 	int fn(int a, int b);
> };
>
> [sub.cpp]
> #include "sub.h"
>
> template<typename T> void Base<T>::dump(T &r)
> {
> }
>
> template<typename T> int Base<T>::fn(int a, int b);
> {
> 	return 0;
> }
>
> [main.cpp]
> #include <stdio.h>
> #include "sub.h"
> #include "TEST.h"
>
> int main()
> {
> 	Base<TEST> t;
> 	TEST x;
>
> 	t.dump(x);
> 	t.fn(1, 2);
> }
>
> ** Result of compiling
> [test@test-1] $ g++ -c -dynamic sub.cpp
> [test@test-1] $ g++ -shared -o libsub.so sub.o
> [test@test-1] $ g++ -g -W -o main main.cpp -lsub -L./
> /tmp/ccaUlqlQ.o: In function `main`:
> /home/guinsa/main.cpp:10: undefined reference to `Base<TEST>::dump(TEST&)`
> /home/guinsa/main.cpp:11: undefined reference to `Base<TEST>::fn(int, int)`
> collect2: ld returned 1 exit status


In your earlier message you said that you had code that worked with gcc
3.4.6 but failed with gcc 4.1.2.  Does this test case work with gcc
3.4.6?

Ian