Question

I’m trying to work with inline assembly but I’m receiving errors..

Here’s a part of the code:

char * buffer = new char[10];
__asm {
    mov ecx,&buffer
    mov edx,07
}

And the errors;

Error 1 error C2400: inline assembler syntax error in ‘second
operand’; found ‘AND’

What I’m doing wrong?

Answer 1

It all depends on what you are trying to achieve.

1. If you are trying to load the addres of the allocated char array into ecx

The value of buffer already is the address you need for ecx. Its something like 0x004F5A42 (just for example) which is the address of the char array in memory, so no reason for having & attached to buffer in your asm code. &buffer would be the address of the buffer pointer itself which in memory may be megabytes away from the char array.

2. If you are trying to load the addres of buffer into ecx

You should probably try this:

char * buffer = new char[10];
char ** buffer_ptr = &buffer;
__asm {
    mov ecx,buffer_ptr
    mov edx,07
}

The reason for this workaround is that, as it appears, the role of & is solely reserved to the AND operator. The following quote is taken from x86 Assembly Language Reference Manual

Operators

The assembler supports the following operators for use in expressions.

…

& Bitwise logical AND

and thereafter & is never mentioned in the manual.