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Unresolved external (old compiler)

I am trying to compile a C program with an ASM procedure. It must be 16-bit, so I use Visual C ++ 1.0 and MASM 6.11.

ASM Code:

.MODEL MEDIUM
EXTRN first:WORD, second:WORD, third:WORD
.CODE
_Add_Ext PROC FAR
    mov AX, first
    add AX, second
    mov third, AX
_Add_Ext ENDP
END

I compiled it in a .obj file

ml.exe -c -Cx -FoC:\prjcts\2_6\2_7.obj C:\prjcts\2_6\2_7.asm

and included in the project.

C code:

#include <stdio.h>
int first = 1, second = 2, third = 0;
void main (void)
{
    printf("\nBefore adding third = %d", third);
    Add_Ext();
    printf("\nAfter adding third = %d", third);
}

When I try to compile it, it gives me:

Compiling...
c:\prjcts\2_6\2_6.c
Linking...

C:\PRJCTS\2_6\2_7.OBJ(C:\prjcts\2_6\2_7.asm) : error L2029: 'first' : unresolved external
C:\PRJCTS\2_6\2_7.OBJ(C:\prjcts\2_6\2_7.asm) : error L2029: 'third' : unresolved external
C:\PRJCTS\2_6\2_7.OBJ(C:\prjcts\2_6\2_7.asm) : error L2029: 'second' : unresolved external

LINK returned error code 2.
Creating browser database...
2_6.EXE - 3 error(s), 0 warning(s)

So, he sees mine .obj, understands what it is, but cannot understand, take variables from C-code? I do not want to use the built-in assembler, but I tried it before and it worked.

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2 answers

In a simple guess, it will be Cman. Extern in C will tend to precompress with

EXTRN _first:WORD, _second:WORD, _third:WORD
+4

! , Microsoft C - , V++ 1.0

.

.MODEL MEDIUM
EXTRN _first:WORD, _second:WORD, _third:WORD
.CODE
_Add_Ext PROC FAR
    mov AX, _first
    add AX, _second
    mov _third, AX
_Add_Ext ENDP
END
0

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