Re: static class member as interrupt handler works, but not if class is templated

Jonathan Wakely via Gcc-help <[email protected]> Sat, 10 Apr 2021 16:26:44 +0100
Newsgroups gmane.comp.gcc.help,gmane.comp.hardware.avr.gcc
Message-ID <CAH6eHdTbVcgqMmJG=bW-pSf5ctHeuYp6HZrA=LxzH5obgLGawQ@mail.gmail.com>
On Sat, 10 Apr 2021, 15:07 Klaus Rudolph via Gcc-help, <[email protected]>
wrote:

> Hi all,
>
> if I write a class with static member function I can use it as an
> interrupt handler as follows:
>
> class Dummy
> {
>      static void Handler() __asm__("__vector_10")
> __attribute__((__signal__, __used__, __externally_visible__));
> };
>
> void Dummy::Handler()
> {
>
> }
>
> I can see the vector is entered in the handler table:
>
>
>
>    1c:  0c 94 34 00     jmp     0x68    ; 0x68 <__bad_interrupt>
>    20:  0c 94 34 00     jmp     0x68    ; 0x68 <__bad_interrupt>
>    24:  0c 94 34 00     jmp     0x68    ; 0x68 <__bad_interrupt>
>    28:  0c 94 36 00     jmp     0x6c    ; 0x6c <__vector_10>
>    2c:  0c 94 34 00     jmp     0x68    ; 0x68 <__bad_interrupt>
>    30:  0c 94 34 00     jmp     0x68    ; 0x68 <__bad_interrupt>
>
> ###################
>
> But if the class becomes a template, the function is not longer entered
> in the handler. How can I fix it?
>
> template < int i >
> class Dummy
> {
>      static void Handler() __asm__("__vector_10")
> __attribute__((__signal__, __used__, __externally_visible__));
> };
>
> template < int i>
> void Dummy<i>::Handler()
> {
>
> }
>
> Dummy<1> d1;
>

This doesn't cause the instantiation of the member function.

Have you tried an explicit instantiation?

template class Dummy<1>;