Re: [avr-chat] SFRs in assembly code

[Heike C. Zimmerer]

"Daniel Otte" <address@hidden> writes:

> It seems that the preprocessor of gas doesn't handle the UL suffix correct.
>
> #define UBRR_VALUE  ((((F_CPU) + (8 * (BAUD)))/ (16 * (BAUD))) -1)
>
> works, while
>
> #define UBRR_VALUE ((((F_CPU) + (8UL * (BAUD))) /(16UL * (BAUD))) -1UL)
>
> yields a lot of " Error: missing ')'" messages.
>
> can anyone verify that?

Yes. indeed, the error message is triggered by the 'UL'.  The simple
assembler line

 .equ test, (34UL)

gives (among others) 

 ./added/fastload.h: Assembler messages:
 ./added/fastload.h:203: Error: missing ')'

> Should I file a bug report for gas?

No.  While you can use the C preprocessor with gas, you cannot use C
constructs with gas.  34UL is not a valid gas constant, since gas
doesn't know anything about things like 'unsigned long' (and it would
have no meaning whatsoever in it).

This #define is meant for use with C and only expands to something
meaningful when used in C.  The error messages you've got are somewhat
misleading, however.  My above test line gave after the part cited
above:

 ./added/fastload.h:203: Error: junk at end of line, first unrecognized
 character is `U'

which points to the problem.


Heike