I have assembled a file using NASM with the following config:

nasm -f obj mmx.asm

which spits out a file named mmx.obj (NASM describes this switch as producing: "MS-DOS 16-bit/32-bit OMF object files")

I have linked this succesfully into a lib compiled by DMC++ which includes the following header to provide access to the asm stuff:

void __cdecl mmx_memcpy(void *d,void *s,int bytes);
void __cdecl mmx_convert_32_to_32_bgr888(void *d,void *s,int pixels);
void __cdecl mmx_convert_32_to_24_rgb888(void *d,void *s,int pixels);
void __cdecl mmx_convert_32_to_24_bgr888(void *d,void *s,int pixels);
void __cdecl mmx_convert_32_to_16_rgb565(void *d,void *s,int pixels);
void __cdecl mmx_convert_32_to_16_bgr565(void *d,void *s,int pixels);
void __cdecl mmx_convert_32_to_16_rgb555(void *d,void *s,int pixels);
void __cdecl mmx_convert_32_to_16_bgr555(void *d,void *s,int pixels);

The lib builds fine but when I then goto to use it in a project I get the following upon attempting to build it:

  Building Blit.exe
	link /SILENT /DELEXECUTABLE /EXET:NT /SU:WINDOWS main.obj ,Blit.exe,,tinyptc.lib,,

OPTLINK (R) for Win32  Release 7.50B1
Copyright (C) Digital Mars 1989 - 2001  All Rights Reserved

G:\Libraries\TinyPTC\lib\tinyptc.lib(convert)
 Error 42: Symbol Undefined ?mmx_convert_32_to_16_rgb555@@YAXPAX0H@Z (void cdecl mmx_convert_32_to_16_rgb555(void *,void *,int ))
G:\Libraries\TinyPTC\lib\tinyptc.lib(convert)
 Error 42: Symbol Undefined ?mmx_convert_32_to_16_bgr565@@YAXPAX0H@Z (void cdecl mmx_convert_32_to_16_bgr565(void *,void *,int ))
G:\Libraries\TinyPTC\lib\tinyptc.lib(convert)
 Error 42: Symbol Undefined ?mmx_convert_32_to_16_rgb565@@YAXPAX0H@Z (void cdecl mmx_convert_32_to_16_rgb565(void *,void *,int ))
G:\Libraries\TinyPTC\lib\tinyptc.lib(convert)
 Error 42: Symbol Undefined ?mmx_convert_32_to_24_rgb888@@YAXPAX0H@Z (void cdecl mmx_convert_32_to_24_rgb888(void *,void *,int ))
G:\Libraries\TinyPTC\lib\tinyptc.lib(convert)
 Error 42: Symbol Undefined ?mmx_memcpy@@YAXPAX0H@Z (void cdecl mmx_memcpy(void *,void *,int ))
SMAKE fatal error: command "link" returned with error code 5
Stopping.

OK so I'm confused...  Why doesn't it spit erros when I build the lib in the first place if there's a problem??  It's 6:36AM and I haven't slept yet trying figure this out so please ease my pain.

Regards,
Tristan Ward

Tristan Ward wrote:

> I have assembled a file using NASM with the following config:
> 
> nasm -f obj mmx.asm
> 
> which spits out a file named mmx.obj (NASM describes this switch as producing: "MS-DOS 16-bit/32-bit OMF object files")
> 
> I have linked this succesfully into a lib compiled by DMC++ which includes the following header to provide access to the asm stuff:
> 

#ifdef __cplusplus
extern "C" {
#endif
> void __cdecl mmx_memcpy(void *d,void *s,int bytes);
> void __cdecl mmx_convert_32_to_32_bgr888(void *d,void *s,int pixels);
> void __cdecl mmx_convert_32_to_24_rgb888(void *d,void *s,int pixels);
> void __cdecl mmx_convert_32_to_24_bgr888(void *d,void *s,int pixels);
> void __cdecl mmx_convert_32_to_16_rgb565(void *d,void *s,int pixels);
> void __cdecl mmx_convert_32_to_16_bgr565(void *d,void *s,int pixels);
> void __cdecl mmx_convert_32_to_16_rgb555(void *d,void *s,int pixels);
> void __cdecl mmx_convert_32_to_16_bgr555(void *d,void *s,int pixels);
#ifdef __cplusplus
}
#endif

> The lib builds fine but when I then goto to use it in a project I get the following upon attempting to build it:
> 
>   Building Blit.exe
>     link /SILENT /DELEXECUTABLE /EXET:NT /SU:WINDOWS main.obj ,Blit.exe,,tinyptc.lib,,
> 
> OPTLINK (R) for Win32  Release 7.50B1
> Copyright (C) Digital Mars 1989 - 2001  All Rights Reserved
> 
> G:\Libraries\TinyPTC\lib\tinyptc.lib(convert)
>  Error 42: Symbol Undefined ?mmx_convert_32_to_16_rgb555@@YAXPAX0H@Z (void cdecl mmx_convert_32_to_16_rgb555(void *,void *,int ))

Looks like a mangled C++ name. Put the extern "C" bracketing around your functions and rebuild.


-scooter

Thanks for your reply scooter.

I tried what you sugested and that at least made the 'Symbol Undefined' errors go away however, I now get a whole stack of these errors instead:

G:\Libraries\TinyPTC\lib\tinyptc.lib(mmx)
 Error 41: Unrecognized FIXUPP Type at Relative 000C9H  from
 Segment text
 FRAME  = Frame of TARGET 00000H
 TARGET = Segment data 08074H
 FIXUPP Type = 16-bit Offset
...

I checked the OPTLINK section of the manual and found this most helpful description:

Unrecognized FIXUPP Type
Most likely cause is the object file has been corrupted, or a translator error has occurred.

I'm afraid that this doesn't tell me much.  I'm teaching myself about all this stuff and so messages like that which may of course mean plenty to a seasoned pro mean next to nothing to me.  What the hell is a FIXUP? ;)

OK so I figured I would pull on my powers of deduction...  'object file corrupted' if thats refering to the .obj that I got nasm to spit out then I can understand that, nasm is the unkown quantity here for me so maybe I need to use different switches or something for it, I don't know yet.  As for 'translator error'...what the translator?

What really confuses me is why the .lib that the mmx.obj is linked into builds fine...surely if there was something wrong with the .obj that nasm is spitting out then the library itself wouldnt build...

Here's an example of some of the asm.  I have taken what looks like relevant information about 1 of the asm functions and stuck it together:

bits 32

global _mmx_memcpy
...
...

section .text

align 16

_mmx_memcpy:

    push ebp
    mov ebp,esp

    pushad

    mov edi,[ebp+8]       ; destination
...
...

If I take out the mmx asm section then all works fine, lib builds, and my prog using the lib build.  But I would really like to make use of the optimised asm routines as they offer quite a significant performance boost.

Anyway, thanks for taking a shot at helping me.

Regards,
Tristan Ward
-scooter- wrote:
> Tristan Ward wrote:
> 
>> I have assembled a file using NASM with the following config:
>>
>> nasm -f obj mmx.asm
>>
>> which spits out a file named mmx.obj (NASM describes this switch as producing: "MS-DOS 16-bit/32-bit OMF object files")
>>
>> I have linked this succesfully into a lib compiled by DMC++ which includes the following header to provide access to the asm stuff:
>>
> 
> #ifdef __cplusplus
> extern "C" {
> #endif
> 
>> void __cdecl mmx_memcpy(void *d,void *s,int bytes);
>> void __cdecl mmx_convert_32_to_32_bgr888(void *d,void *s,int pixels);
>> void __cdecl mmx_convert_32_to_24_rgb888(void *d,void *s,int pixels);
>> void __cdecl mmx_convert_32_to_24_bgr888(void *d,void *s,int pixels);
>> void __cdecl mmx_convert_32_to_16_rgb565(void *d,void *s,int pixels);
>> void __cdecl mmx_convert_32_to_16_bgr565(void *d,void *s,int pixels);
>> void __cdecl mmx_convert_32_to_16_rgb555(void *d,void *s,int pixels);
>> void __cdecl mmx_convert_32_to_16_bgr555(void *d,void *s,int pixels);
> 
> #ifdef __cplusplus
> }
> #endif
> 
>> The lib builds fine but when I then goto to use it in a project I get the following upon attempting to build it:
>>
>>   Building Blit.exe
>>     link /SILENT /DELEXECUTABLE /EXET:NT /SU:WINDOWS main.obj ,Blit.exe,,tinyptc.lib,,
>>
>> OPTLINK (R) for Win32  Release 7.50B1
>> Copyright (C) Digital Mars 1989 - 2001  All Rights Reserved
>>
>> G:\Libraries\TinyPTC\lib\tinyptc.lib(convert)
>>  Error 42: Symbol Undefined ?mmx_convert_32_to_16_rgb555@@YAXPAX0H@Z (void cdecl mmx_convert_32_to_16_rgb555(void *,void *,int ))
> 
> 
> Looks like a mangled C++ name. Put the extern "C" bracketing around your functions and rebuild.
> 
> 
> -scooter
> 

It probably means you're mixing 16 and 32 bit code. In your asm code, make sure it is set to generate 32 bit code, not 16 bit code.