Re: Bug with SDCC and in-line assembler labels?

SDCC is open source and always a work in progress.

Alothough it is quite mature.

What version do you have?

Do you have latest offical release and not an unproven nightly snap shot
beta?

JG

"Desert Rat" <rhunt@xxxxxxxxxxxxxxxxxx> wrote in message
news:1143735545.336541.79720@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
If you use in-line assembly language within a SDCC program, are you
limited to the types of labels you may use if the assembler code
branches?

As an example, the following "do-nothing" program compiles and
assembles just fine:

void main(void)
{
_asm
nop
nop
nop
_endasm;
}

The following program, with an assembler label and a jump instruction,
also compiles and assembles without error:

void main(void)
{
_asm
nop
alabel:
nop
ljmp alabel
nop
_endasm;
}

But this code, although it compiles just fine, generates an "undefined
symbol encountered during assembly" error:

void main(void)
{
char i;
if (i == 1)
{
_asm
nop
alabel:
nop
ljmp alabel
nop
_endasm;
}
}

The problem is that SDCC generates the ".asm" file with labels of the
form "0xxxx$:", where xxxx is some number. The "alabel" label creates
a barrier between code above it and code below it. The IF statement
generates code above "alabel" which references the compiler-generated
label below "alabel", and cannot find it.

If you change the program to use a label of the form "0xxxx$" it
compiles and assembles fine again:

void main(void)
{
char i;
if (i == 1)
{
_asm
nop
01000$:
nop
ljmp 01000$
nop
_endasm;
}
}

Is there a way around this problem? Interestingly enough, the SDCC
manual shows an example of in-line assembler with a "normal" label.



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