Lpc2000

Hello,

for reducing code size (120 KB is not enough...) i tried to compile some
parts of my code as thumb code, the other as arm code. It does not work,
linker always tells me: "libgcc.a does not support interworking, whereas
callthumb does."

Searching through the net for a solution, i found there is something like a
thumb-elf-gcc. Do i need this special gcc, additional to my arm-elf-gcc ? I
always thought that arm-elf-gcc supports both modes and i can
use -mthumb-interwork and -mthumb for doing this. If i need this, where can
i get a version for cygwin (best case in version 3.4 of gcc) ?

Has someone knowledge on this topic and already tried it successfully ? Is
there a special mailinglist for arm-elf-gcc / thumb-elf-gcc ?

Greetings,

          Martin

At 18:01 2004-01-09, you wrote:
>Hello,
>
>for reducing code size (120 KB is not enough...) i tried to compile some
>parts of my code as thumb code, the other as arm code. It does not work,
>linker always tells me: "libgcc.a does not support interworking, whereas
>callthumb does."
>Searching through the net for a solution, i found there is something like a
>thumb-elf-gcc. Do i need this special gcc, additional to my arm-elf-gcc ?

  You need to enable thumb interworking in your toolchain. 
"arm-thumf-elf-gcc" is just arm-elf-gcc with thumb enabled by default.

>I
>always thought that arm-elf-gcc supports both modes and i can
>use -mthumb-interwork and -mthumb for doing this.

  What toolchain are you using?

>Has someone knowledge on this topic and already tried it successfully ? Is
>there a special mailinglist for arm-elf-gcc / thumb-elf-gcc ?

  Yes, the GCC mailing list. Also check out the GCC ARM improvement project 
(http://sed.inf.u-szeged.hu/gcc-arm/index.php).

  Regards.


--
PabloBleyerKocik /"Mama said to get things done
  pbleyer        / you better not mess with major Tom"
   @... / -- Ashes to ashes, David Bowie

> You need to enable thumb interworking in your toolchain. 
> "arm-thumf-elf-gcc" is just arm-elf-gcc with thumb enabled by default.

Has there ever been any thought towards an __attribute__ to declare a
function as ARM or THUMB?  The silicon has good support for moving
between ARM and THUMB, but unless I'm missing something, the compiler
support (CallThumb) is very awkward.  Explicitly declaring functions
would sure be easier.