PRB: Inline Assembly C++ Function May Need Return Statement
Article ID: 107432
Article Last Modified on 12/2/2003
APPLIES TO
- Microsoft C/C++ Professional Development System 7.0
- Microsoft Visual C++ 1.0 Professional Edition
- Microsoft Visual C++ 1.5 Professional Edition
- Microsoft Visual C++ 2.0 Professional Edition
This article was previously published under Q107432
SYMPTOMS
C++ functions containing inline assembly routines that store the
return value in the AX register may need a return statement added to
the function. If the function does not have a return statement, the
following error is generated:
C2561: 'function name' function must return a value
RESOLUTION
To resolve this error, create a temporary variable and move the AX
register to this variable for the return statement. This will work
around the C++ type-checking syntax. If you are using C++ version 8.0
that ships with Visual C++ for Windows NT, then the EAX register must
be used instead.
Sample Code
/* Compile options needed: none
*/
int func(void)
{
//int a; //Remove this comment to eliminate the error.
__asm
{
mov ax, 02h
;mov a, ax //Remove this comment to eliminate the error.
}
//return a; //Remove this comment to eliminate the error.
}
void main(void)
{
int a;
a = func();
}
Additional query words: 7.00 8.00 8.00c 9.00 1.00 1.50 2.00
Keywords: kbprb KB107432