[En-Nut-Discussion] Class constructor doesn't execute

[Krzysztof Sawicki]

On 05.12.2016 14:59, Uwe Bonnes wrote:
>>>>>> "Krzysztof" == Krzysztof Sawicki <krzysztof.sawicki at mlabs.pl> writes:
>
>     Krzysztof> Hi, recently I tried some C++ with NutOS and realised that
>     Krzysztof> class' constructors are not executed. I did some research and
>     Krzysztof> realised that following code fixes this issue:
>
>     Krzysztof> in linker script add: .preinit_array : { PROVIDE_HIDDEN
>     Krzysztof> (__preinit_array_start = .); KEEP (*(.preinit_array*))
>     Krzysztof> PROVIDE_HIDDEN (__preinit_array_end = .); } > FLASH0
>    	
>     Krzysztof>    	.init_array : { PROVIDE_HIDDEN (__init_array_start =
>     Krzysztof> .); KEEP (*(SORT(.init_array.*))) KEEP (*(.init_array*))
>     Krzysztof> PROVIDE_HIDDEN (__init_array_end = .); } > FLASH0
>    	
>     Krzysztof>    	.fini_array : { PROVIDE_HIDDEN (__fini_array_start =
>     Krzysztof> .); KEEP (*(SORT(.fini_array.*))) KEEP (*(.fini_array*))
>     Krzysztof> PROVIDE_HIDDEN (__fini_array_end = .); } > FLASH0
>
>     Krzysztof> in main() at the beginning add: /* Call static constructors
>     Krzysztof> */ asm("bl __libc_init_array");
>
>
>     Krzysztof> and anywhere in the code:
>
>     Krzysztof> 	extern "C" { void *__dso_handle = NULL; void _init(void){} }
>
>
> Why does app/cppdemo build?
>
> What of these prerequisites is Gnu specific, what is processor specific and
> what is generic. I think anything generic can be added guarded with
> #if defined(__cpluplus)
>
> Any ideas?

app/cppdemo builds, but I tried such code:

...
class A
{
     public:
     A() {ab=123;}
     void print(FILE *stream) {fprintf(stream,"ab=%d\n",ab);}
     int ab;
};

A A1;


int main(void) {
     u_long baud = 115200;

     NutRegisterDevice(&DEV_CONSOLE, 0, 0);
     FILE *stream = fopen(DEV_CONSOLE.dev_name, "r+");
     _ioctl(_fileno(stream), UART_SETSPEED, &baud);

     fprintf(stream, "\n\nC++ Demo on Nut/OS %s ready.\n", NutVersionString());

     Counter counter(58);
     counter.print(stream);

     A A2;
     A1.print(stream);
     A2.print(stream);
...


and got on terminal:

C++ Demo on Nut/OS 5.2.4.0 ready.

Counter value = 58
ab=0
ab=123

How to solve this problem, any ideas?

greetings
-- 
Krzysztof Sawicki
MLabs sp. z o.o.
ul. Kaliska 21
61-131 Poznań

tel. 61 646 84 27

KRS: 0000390306
NIP: 7822533401