proc asdfgh
ret
endp

From PROC32.INC:
macro proc [args] ; define procedure
{ common
match name params, args>
\{ define@proc name,<params \} }
...
[skip]
...
macro define@proc name,statement
{ local params,flag,regs,parmbytes,localbytes,current
if used name
name:
...

In code:
call asdfgh
will preprocess proc to:
asdfgh: ret

But if proc unused it must be preprocess to:
ret ;without label

In fact if proc unused it preprocess to nouthing.

Why unused proc exclude from source? Where this line in PROC32.INC?

EDIT by DOS386 : moved from Main to Macroinstructions

This feature was once requested by users and since then it became a standard behavior of "proc". It is the "if used name" line that causes this (if you decide to remove it, you also have to remove the "end if" that pairs to it, it is the one at the end of "finish@proc" macro).

if you wish to leave proc in binary file you may use something like this:

To Tomasz:
Yes, in fist time I made this. After I find another way.

But question in this:

MyMacro
... any code here <- this code don't exclude in any way
MyMacro2

but

proc label <- macro
... any code here <- may be exclude !!!!!!!!!!!!!!!!!!!!!!!!
endp <- macro

Is it feature of macro or fasm core? In which stage fasm leave out code.

macro MyMacro {
if ~ used Name
virtual
end if
}

macro MyMacro2 {
if ~ used Name
end virtual
end if
}

In this case code between MyMacro and MyMacro2 will be skip.
But I find nothing of the kind in PROC32.INC

Who cut code between proc and endp macro?

It is done this way:

Yes!
end if <- in macro finish@proc called from endp macro.

end if \} } <- in macro
\} end if } <- in my mind, sorry...

Thanks!