Re: Newlib 1.8.1 vfprintf problem on embedded PowerPC

[Jay Kulpinski <jskulpin@eng01.gdds.com>]

Roger Williams wrote:
> 
> Hi --
> 
> While waiting for my s/w guru to develop application code, I'm writing
> hardware debug utilities for my embedded MPC860 hardware.  With the
> help of the CrossGCC FAQ, it was a simple matter to build GCC 2.8.1
> and Newlib 1.8.1 and get a simple "Hello, world" program running.
> 
> Most of the libc functions, including sscanf, etc., work fine.
> However, any call to vfprintf goes off to Never-Never Land, so sprintf
> doesn't work.
> 
> Any ideas about where to start looking?  The printf innards are rather
> hairy...  (Unfortunately, I don't have access to an ICD right now, so
> my job is even tougher.)
> 
> Am I right in assuming that printf et al. are working for other
> powerpc-eabi developers?
> 
> --
> Roger Williams                         finger me for my PGP public key
> Coelacanth Engineering Inc    consulting & turnkey product development
> Middleborough, Massachusetts           wireless * datacomm * DSP * ATE
> tel +1 508 947-5585 * fax +1 508 861-0278 * http://www.coelacanth.com/

This probably isn't your problem, but you should fix this
in your source.  It can trash the stack and take you down 
quite easily.  This problem shows up when printing denormalized
doubles. 

(616)% diff -c newlib-1.8.1/newlib/libc/stdlib/mprec.c{-orig,}
*** newlib-1.8.1/newlib/libc/stdlib/mprec.c-orig        Wed May 12
11:43:46 1999
--- newlib-1.8.1/newlib/libc/stdlib/mprec.c     Wed May 12 11:45:08 1999
***************
*** 763,769 ****
--- 763,771 ----
    unsigned long *x, y, z;
  #ifdef VAX
    unsigned long d0, d1;
+ #endif
    d.d = _d;
+ #ifdef VAX
    d0 = word0 (d) >> 16 | word0 (d) << 16;
    d1 = word1 (d) >> 16 | word1 (d) << 16;
  #else
_______________________________________________
New CrossGCC FAQ: http://www.objsw.com/CrossGCC
_______________________________________________
To remove yourself from the crossgcc list, send
mail to crossgcc-request@cygnus.com with the
text 'unsubscribe' (without the quotes) in the
body of the message.