Key problem is the Macro-Args with mlti line,Just copy-paste is enough

macro SUB_RSP vars{
vars
PRINT_VAL
}


entry _start
_start:
SUB_RSP {mov rax,5
PRINT_VAL
}

main.asm [551]:
SUB_RSP {mov rax,5
error: invalid macro arguments.

Try <>,&,\,withspace,withoutspace didn't work.
Read posts didn't found.

Originally Want to define vars on stack without too many lines

macro SString bodys {
virtual at rsp
;; str String
;; str_size =$-str
bodys
end virtual

sub rsp,str_size
mmap 0,STRING_INIT_CAP,PROT_READ or PROT_WRITE,MAP_PRIVATE or MAP_ANONYMOUS,-1,0
cmp r0,MAP_FAILED
je gg
mov [str#.items],r0
add [str#.capacity],STRING_INIT_CAP
add rsp,str_size
}

Here is my Liunx x86_64 syscall macro
Free to use

;;rdi,rsi,rdx,r10,r8,r9
sc_var_pos = 0
macro sc_var number, [args] {
common
mov r0, number
forward
if ~ args eq
if sc_var_pos = 0
mov r1, args
push r1
else if sc_var_pos = 1
mov r2, args
push r2
else if sc_var_pos = 2
mov r3, args
push r3
else if sc_var_pos = 3
mov r4, args
push r4
else if sc_var_pos = 4
mov r5, args
push r5
else if sc_var_pos = 5
mov r6, args
push r6
end if
end if
sc_var_pos = sc_var_pos + 1
common
sc
if sc_var_pos > 5
pop r6
end if
if sc_var_pos > 4
pop r5
end if
if sc_var_pos > 3
pop r4
end if
if sc_var_pos > 2
pop r3
end if
if sc_var_pos > 1
pop r2
end if
if sc_var_pos > 0
pop r1
end if

sc_var_pos = 0
}

The general case is this:

Huge Thanks! ypa!!!