MRB_BEGIN_DECL trouble mruby 3.1.0

[bialystok]

I embeded mruby in cpp program (Linux fedora)
my main program is : g++ -W -Wall -pedantic -O0 -I . -I ~/mruby/include/ -I ~/mruby/include/mruby -c main.cpp -lm -o main.o

----main.cpp----

#include <iostream>
#include "tfunkcje.h"

int main()
{
m_start();
std::cout << "suma 1+8 = " << m_suma(1,8) << "\n";
m_stop();

return 0;
}

--- tfunkcje.h

extern "C" {

#include <mruby.h>
#include <mruby/irep.h>

int  m_start();
int  m_suma(int a,int b);
void m_stop();

}

I get error. Probably declaration are using in mruby but mruby not including it.
deleting MRB_END_DECL on endian delete errors

---

In file included from /usr/include/sys/types.h:176,
from /usr/include/stdlib.h:395,
from /usr/include/c++/12/cstdlib:75,
from /usr/include/c++/12/ext/string_conversions.h:41,
from /usr/include/c++/12/bits/basic_string.h:3968,
from /usr/include/c++/12/string:53,
from /usr/include/c++/12/bits/locale_classes.h:40,
from /usr/include/c++/12/bits/ios_base.h:41,
from /usr/include/c++/12/ios:42,
from /usr/include/c++/12/ostream:38,
from /usr/include/c++/12/iostream:39,
from main.cpp:1:
/home/user/mruby/include/mruby/endian.h:12:1: error: ‘MRB_BEGIN_DECL’ does not name a type
12 | MRB_BEGIN_DECL
| ^~~~~~~~~~~~~~
/home/user/mruby/include/mruby/endian.h:12:1: note: the macro ‘MRB_BEGIN_DECL’ had not yet been defined
In file included from /home/user/mruby/include/mruby.h:116,
from tfunkcje.h:3,
from main.cpp:2:
/home/user/mruby/include/mruby/common.h:21: note: it was later defined here
21 | # define MRB_BEGIN_DECL extern "C" {
|
In file included from /home/user/mruby/include/mruby.h:118:
/home/user/mruby/include/mruby/gc.h:51:9: warning: ISO C++ forbids flexible array member ‘objects’ [-Wpedantic]
51 | void *objects[];
| ^~~~~~~
make: *** [Makefile:68: main.o] Błąd 1

-------tfunkcje.cpp-----this compiled corectly----

#include <tfunkcje.h>

 mrb_state *mrb;

int m_start()
{
char kod[] = "def suma(a,b) (a+b).to_i end";
 mrb = mrb_open();

 if (!mrb) { return 1; }
 mrb_load_string(mrb, kod);

return 0;
}

void m_stop()
{
 mrb_close(mrb);
}

int m_suma(int a, int b)
{
mrb_value c;

   c = mrb_funcall(mrb, mrb_top_self(mrb), "suma",
                        2,mrb_fixnum_value(a),mrb_fixnum_value(b));

return mrb_int(mrb, c);
}

[dearblue]

1. It is not desirable to add mruby/include/mruby as an include directory.

   Because the file mruby/include/mruby/endian.h may hide /usr/include/endian.h on your system.

   -g++ -W -Wall -pedantic -O0 -I . -I ~/mruby/include/ -I ~/mruby/include/mruby -c main.cpp -lm -o main.o
   +g++ -W -Wall -pedantic -O0 -I . -I ~/mruby/include/ -c main.cpp -lm -o main.o

2. May need #include <mruby.h> before the standard library header files.

   Although mruby requires the C standard definition, it may not be defined if the C++ standard header file appears first.

   +#include "tfunkcje.h"
    #include <iostream>
   -#include "tfunkcje.h"