[Tinyos-devel] ti msp430 cc

[Razvan Musaloiu-E.]

Hi!

On Thu, 13 Nov 2008, David Gay wrote:

> 2008/11/12 Razvan Musaloiu-E. <razvanm at cs.jhu.edu>:
>> Hi!
>>
>> On Tue, 11 Nov 2008, Geoffrey Werner-Allen wrote:
>>
>>> Hi Martin, Steve:
>>>
>>> We had heard at Sensys'08 that someone had written a script to strip the
>>> GCC-specific stuff out of the nesc output C code so that it could be fed
>>> through another compiler.
>>
>> The only thing that I'm aware of that does this it the mangleAppC.pl from
>> the tinyos-2.x for 8051. The script can be retrieve using the following svn
>> checkout command:
>>        svn co svn://svn.tinyos8051wg.net/repos/tinyos-2.x-contrib/trunk/diku/mcs51/support/make/mcs51
>> Note: in the same directory there are two big .exe file, one of 2MB and
>> another one of 6MB, so the download will take a little time.
>>
>> Martin Leopold can say more about how feasible is to use this for MSP430.
>> From my point of view this is a wrong direction. The right one would be to
>> do change nesc to generate ANSI C code. :-)
>
> To the best of my knowledge, it does generate ISO C99 code. AFAIK,
> there's five issues with non-gcc compilers (the $ doesn't count any
> more, just use -fnesc-separator=__):
> - Does the compiler support inline? If it doesn't, then you'll have
> performance problems (this is an issue for the 8051 compilers)

This is something important but not a blocking thing.

> - Do you want to use it for tossim with a compiler that doesn't follow
> ISO C99? (the initializers for module variables with tossim use the
> new '(type) { initializers }' syntax)
>  [inline and these initializers are the only uses of non-ANSI/ISO C90
> features in actual code generation]

Tossim is compiled with the host compiler and gcc is more than than fine 
for that. Right?

> - Do you want ncc/nescc to behave like gcc and convert options to your
> compiler's driver, or do you want a ncc/nescc replacement that behaves
> more like your compiler's driver? (both require a little but not that
> much work)

I think any of the solution is fine. As a developer I rarely run ncc/nescc 
by hand because everything is taking care by the Makefile infrastructure.

> - Is TinyOS using some C syntax your compiler doesn't support? (this
> is an issue for TinyOS, AFAIK it's not a major problem)

Right.

> - Does your C compiler come with its own C extensions that you need
> nesC to support? (this can be necessary because of header files or
> because you need those extensions in the code you want to write - this
> was the major issue for 8051 compilers which have lots of C extensions
> to deal with the 8051 architecture)

Yes. SDCC, IAR, Keil have special extensions that nesC needs to know 
about.

> So, figure out the answers to those questions, and give it a try...
> And if you want to make any changes to nesC to address any of these
> I'm happy to incorporate patches, or even better have you maintain the
> other compiler's nesC support (to be frank, this was always the major
> issue with 8051 support)

Let's say that my main target would be SDCC for 8051. What things should I 
change in nesc to get a app.c that compiles correctly? :-)

--
Razvan ME