• lili (29/29) Aug 24 2019 Hi:
• a11e99z (6/35) Aug 24 2019 resb 8
• lili (3/10) Aug 24 2019 I write wrong, not if (_vga_x == _vga_y) but if (&_vga_x ==
• a11e99z (9/20) Aug 24 2019 try to do next:
• lili (11/32) Aug 25 2019 I followed your suggest, call asm_fn in d function. it return
• a11e99z (14/47) Aug 25 2019 no idea.
• a11e99z (3/5) Aug 25 2019 and try to use any compiler DMD/LDC/GDC.

lili <akozhao tencent.com> writes:

Hi:
   definition _vga_x and _vga_y symbol in asm, compile use nasm -f 
elf64 -o boot.o boot.asm
   [section .bss]
     ...

   [global _vga_x]
   _vga_x:
           resb 8
   [global _vga_y]
   _vga_y:
           resb 8


   and nm boot.o show below
     ...
    00107000 B _vga_x
    00107008 B _vga_y

  and In another D file use this two symbol

extern(C) {
  extern __gshared int _vga_x; //definition in boot.asm
  extern __gshared int _vga_y; //definition in boot.asm
}

  void tt()
  {
     if (_vga_x == _vga_y)
       //where is true, why?
  }

  but when a run tt so strange things happend that the test is 
true.
  Is where has a coding mistake.
  src  https://github.com/lilijreey/OS-D

a11e99z <black80 bk.ru> writes:

On Saturday, 24 August 2019 at 11:53:01 UTC, lili wrote:
 Hi:
   definition _vga_x and _vga_y symbol in asm, compile use nasm 
 -f elf64 -o boot.o boot.asm
   [section .bss]
     ...

   [global _vga_x]
   _vga_x:
           resb 8
   [global _vga_y]
   _vga_y:
           resb 8


   and nm boot.o show below
     ...
    00107000 B _vga_x
    00107008 B _vga_y

  and In another D file use this two symbol

 extern(C) {
  extern __gshared int _vga_x; //definition in boot.asm
  extern __gshared int _vga_y; //definition in boot.asm
 }

  void tt()
  {
     if (_vga_x == _vga_y)
       //where is true, why?
  }

  but when a run tt so strange things happend that the test is 
 true.
  Is where has a coding mistake.
  src  https://github.com/lilijreey/OS-D

resb 8
just reserving 8 bytes not initializing it.
probably u compare some garbage. sometimes it equals, sometimes 
not.
no?

lili <akozhao tencent.com> writes:

On Saturday, 24 August 2019 at 12:09:19 UTC, a11e99z wrote:
 On Saturday, 24 August 2019 at 11:53:01 UTC, lili wrote:
  [...]

 resb 8
 just reserving 8 bytes not initializing it.
 probably u compare some garbage. sometimes it equals, sometimes 
 not.
 no?

I write wrong, not  if (_vga_x == _vga_y) but if (&_vga_x == 
&_vga_y)

a11e99z <black80 bk.ru> writes:

On Saturday, 24 August 2019 at 12:16:34 UTC, lili wrote:
 On Saturday, 24 August 2019 at 12:09:19 UTC, a11e99z wrote:
 On Saturday, 24 August 2019 at 11:53:01 UTC, lili wrote:
  [...]

 resb 8
 just reserving 8 bytes not initializing it.
 probably u compare some garbage. sometimes it equals, 
 sometimes not.
 no?

 I write wrong, not  if (_vga_x == _vga_y) but if (&_vga_x == 
 &_vga_y)

try to do next:
add funtion in asm that returns real addresses to vga_x,y
extern(C) void asmVgas( int** px, int** py)
call it
int *px, *py;
asmVgas( &px, &py);
writefln( "%s=%s,%s=%s",px, &_vga_x,py, &_vga_y);
and see result

lili <akozhao tencent.com> writes:

On Saturday, 24 August 2019 at 12:55:57 UTC, a11e99z wrote:
 On Saturday, 24 August 2019 at 12:16:34 UTC, lili wrote:
 On Saturday, 24 August 2019 at 12:09:19 UTC, a11e99z wrote:
 On Saturday, 24 August 2019 at 11:53:01 UTC, lili wrote:
  [...]

 resb 8
 just reserving 8 bytes not initializing it.
 probably u compare some garbage. sometimes it equals, 
 sometimes not.
 no?

 I write wrong, not  if (_vga_x == _vga_y) but if (&_vga_x == 
 &_vga_y)

 try to do next:
 add funtion in asm that returns real addresses to vga_x,y
 extern(C) void asmVgas( int** px, int** py)
 call it
 int *px, *py;
 asmVgas( &px, &py);
 writefln( "%s=%s,%s=%s",px, &_vga_x,py, &_vga_y);
 and see result

I followed your suggest, call asm_fn in d function. it return 
address not 0 but is a correct
address same as the var address show in link map file.
when a try define a __shared int xx, the &xx also 0.
after linked all variables address is 0 that in .bss segment.
do you know why occur this?

[global asm_fn]
asm_fn:
	mov rax, p2_table
	ret

a11e99z <black80 bk.ru> writes:

On Sunday, 25 August 2019 at 13:24:57 UTC, lili wrote:
 On Saturday, 24 August 2019 at 12:55:57 UTC, a11e99z wrote:
 On Saturday, 24 August 2019 at 12:16:34 UTC, lili wrote:
 On Saturday, 24 August 2019 at 12:09:19 UTC, a11e99z wrote:
 On Saturday, 24 August 2019 at 11:53:01 UTC, lili wrote:
  [...]

 resb 8
 just reserving 8 bytes not initializing it.
 probably u compare some garbage. sometimes it equals, 
 sometimes not.
 no?

 I write wrong, not  if (_vga_x == _vga_y) but if (&_vga_x == 
 &_vga_y)

 try to do next:
 add funtion in asm that returns real addresses to vga_x,y
 extern(C) void asmVgas( int** px, int** py)
 call it
 int *px, *py;
 asmVgas( &px, &py);
 writefln( "%s=%s,%s=%s",px, &_vga_x,py, &_vga_y);
 and see result

 I followed your suggest, call asm_fn in d function. it return 
 address not 0 but is a correct
 address same as the var address show in link map file.
 when a try define a __shared int xx, the &xx also 0.
 after linked all variables address is 0 that in .bss segment.
 do you know why occur this?

 [global asm_fn]
 asm_fn:
 	mov rax, p2_table
 	ret

no idea.

u can to define _vga_x,_vga_y in D code and export it to asm 
(vice versa than now).
see result again.

in case still not working:
make very simple app with global vars: 2 D-files OR 1 D-file and 
1 asm-file
(maybe its not working even for D+D files).
try to get same bug from compiler/linker.
fill the issue and attach both files as sample.
add point (for case D+asm) "how to compile asm file for linking 
with D" as u did.
then wait and hope.

a11e99z <black80 bk.ru> writes:

On Sunday, 25 August 2019 at 13:43:42 UTC, a11e99z wrote:
 On Sunday, 25 August 2019 at 13:24:57 UTC, lili wrote:
 On Saturday, 24 August 2019 at 12:55:57 UTC, a11e99z wrote:


and try to use any compiler DMD/LDC/GDC.
maybe result will be that u want.