proc ...
LOCAL param1 db 0
...
endp    

proc1:
push ebp
mov ebp, esp
sub esp, 8
mov dword [ebp-4], 0x00 ; local var 1
mov dword [ebp-8], 0x01 ; local var 2
...
pop ebp
mov esp, ebp
retn
    

To declare the local variable you can use the local macroinstruction, followed by one or more declarations separated with commas, each one consisting of the name for variable followed by colon and the type of variable – either one of the standard types (must be upper case) or the name of data structure. For example:

local hDC:DWORD,rc:RECT

To declare a local array, you can follow the name of variable by the size of array enclosed in square brackets, like:

local str[256]:BYTE

The other way to define the local variables is to declare them inside the block started with ”locals” macroinstruction and ended with ”endl”, in this case they can be defined just like regular data. This declaration is the equivalent of the earlier sample:

locals
hDC dd ?
rc RECT
endl

The local variables can be declared anywhere inside the procedure, with the only limitation that they have to be declared before they are used. The scope of labels for the variables defined as local is limited to inside the procedure, you can use the same names for other purposes outside the procedure. If you give some initialized values to the variables declared as local, the macroinstruction generates the instructions that will initialize these variables with the given values and puts these instruction at the same position in procedure, where the declaration is placed.

visual studio link.exe linker can parse /align:... parameter

Unfortunately for Microsoft users, if you use /ALIGN, it sets both the in-memory section alignment and the on-disk alignment to the same value (such as 16 bytes). In Windows NT, an executable with 16-byte alignment can run, but you wouldn't want to do this for some low-level techie reasons. Alas, Windows 95 won't run an executable file with sections that aren't aligned on a boundary that's a multiple of 0x1000 bytes.