Re: Automatic variables and implicit rules

[Jess Telford]

Thanks Sam.

Using the defer assignment, I was able to get it to work exactly as I
wanted with;
CFLAGS                =      -g -Wall -O2 -Wa,address@hidden

However, when I added your further enhancement of dropping the suffix,
I was getting a null string again.

Turns out that you forgot the ":" in the middle there. It worked fine
with the following;
CFLAGS                =      -g -Wall -O2 -Wa,-ahl=$(@:.o=.s)

Thank you again for your help.

Cheers,
Jess - http://jt0.org



2008/12/21 Sam Ravnborg <address@hidden>:
>>
>> So, my modified CFLAGS looks like this;
>> CFLAGS                :=      -g -Wall -O2 -Wa,-ahl=file.s
>
> In make there are two different kind of assignments.
> The one you used above ":=" where CFLAGS is assigned the
> the exact value you specify on the time of assignment.
>
>> The best option I can see for this is using the automatic variable 
>> address@hidden
>> Making CFLAGS look like;
>> CFLAGS                :=      -g -Wall -O2 -Wa,address@hidden
>
> And what you want to do here is to tell make to defer the assignmnet
> of CFLAGS unitl you use the variable because only at that
> time you know the value of address@hidden
> To do so use "=" as assignment operator like this:
>
> CFLAGS                =      -g -Wall -O2 -Wa,address@hidden
>
> As an further enhancement you can drop the original
> suffix like this:
> CFLAGS = -g -Wall -O2 -Wa,-ahl=$(@.o=.s)
>
>        Sam
>