interworking problem

interworking problem

[aram bharathi]

hi,
   thanks for identifying the error.
   i have gone through the a.out file after this error. that is producing full of arm instructions other than the main function(which is compiled for -mthumb). where should i change for this corresponding error. 
   i have added one new add instruction in thumb mode. based on that i have written one sample program to emit the corresponding new instruction. gcc works fine. when i assemble the function it emits correct opcode. but when i give the same function to the ld it emits full of arm instructions instead of thumb instructions. which routine checks for this corresponding change. 
thanks in advance  
----- Original Message -----
From: "Ian Lance Taylor" <ian@airs.com>
To: "aram bharathi" <arambharathi@linuxmail.org>
Subject: Re: adding new instruction
Date: 12 Feb 2005 21:06:07 -0500

> 
> "aram bharathi" <arambharathi@linuxmail.org> writes:
> 
> >   i like to add a new instruction based on thumb ISA. i have 
> > added the instruction in both as and gcc. both of them are 
> > working correctly. but when i call ld it shows an error like
> >
> > /home/.../arm-elf-ld : 
> > /home/../arm-elf/lib/libc.a(printf.o)(printf): warning : 
> > interworking not enabled
> > first occurance : /tmp/cc00zhyh.o : thumb call to arm
> > /tmp//cc00zhyh.o(.text+0x4e>: In function 'main'
> > new.c:internal error: dangerous error
> >
> > whether i have to change anything in the ld. i have searched for 
> > the ld source file but i counldnt get one in the ld folder. which 
> > file has to modified first and what kind of changes are needed.
> 
> The source code for that error is in the bfd directory.  In general,
> if you want to link ARM and Thumb code together, you should compile
> all your code with the -mthumb-interwork option.  See the
> documentation.
> 
> Ian

-- 
______________________________________________
Check out the latest SMS services @ http://www.linuxmail.org 
This allows you to send and receive SMS through your mailbox.


Powered by Outblaze

Re: interworking problem

[Nick Clifton]

Hi Aram,

>    i have gone through the a.out file after this error. 
 > that is producing full of arm instructions other than the main
> function(which is compiled for -mthumb). 
> where should i change for this corresponding error. 

It is not clear what question you are asking here.

Ian has pointed out that you should be compiling your program with the 
-mthumb-interwork switch specified on the gcc command line.

>    i have added one new add instruction in thumb mode. based on that
> i have written one sample program to emit the corresponding new 
> instruction. gcc works fine. when i assemble the function it emits 
 > correct opcode. but when i give the same function to the ld it
 > emits full of arm instructions instead of thumb instructions.
 > which routine checks for this corresponding change.

Again this is not clear.  Do you mean that when the linker is creating 
the executable that it is inserting some ARM-encoded instructions into 
the output, or that it is somehow magically transforming your 
THUMB-encoded instructions into ARM-encoded instructions ?

Perhaps it would help if you could provide a *small* example program and 
  the command lines you use to compile it, as well as description of 
what is wrong with the resulting executable.

Cheers
   Nick