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Q65309: In-Line Assembler Locks Up C 6.00

Article: Q65309
Product(s): See article
Version(s): 6.00   | 6.00
Operating System(s): MS-DOS | OS/2
Keyword(s): ENDUSER | buglist6.00 | mspl13_c
Last Modified: 31-AUG-1990

The code below will "lock up" C 6.00 regardless of optimizations.

Using the quick compiler (/qc) will allow the program to compile.

Sample Code
-----------

#define LCPPORT 0
#define COMREQ 0x14
#define FOREVER for(;;)

extern void _far _cdecl delay(int ticks);

void clrlcp(void)
{
int ticks = 4;
   FOREVER
      {
      _asm
         {
         push [ticks]
         call delay
         add sp,2
         mov dx,LCPPORT
         mov ah,7
         int COMREQ
         cmp al,0
         jz done
         mov dx,LCPPORT
         mov ah,6
         int COMREQ
         }
      ticks = 4;
      }
   done: return;
}

Microsoft has confirmed this to be a problem in C version 6.00. We are
researching this problem and will post new information here as it
becomes available.

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