Re: [lwip-users] lwip PPP malloc problem

[Rainer Thaden]

Am 21.07.2014 14:02, schrieb Simon Goldschmidt:
> Rainer Thaden wrote:
>> Since I need to communicate over serial ports, too, I activated PPP
>> support in lwipopts.h.
>> Now, the linker complains about undefined references to _sbrk which (to
>> me) is a sign for a call to malloc in the libc somewhere.
> Check your linker file if it tells you why _sbrk is wanted. At least gcc has 
> some good output in the map file for this. I think I remember to get malloc 
> include when calling printf...
>

Thanks Simon, I forgot to mention, I looked into the map file, but it
didn't give me the answer that I was looking for. (see below).

The printf seems to be a good hint. Thanks for that!

Regards,

Rainer

Output from map-file:

c:/progra~1/codesourcery/sourcery_codebench_lite_for_arm_eabi/bin/../lib/gcc/arm-none-eabi/4.7.3/../../../../arm-none-eabi/lib/thumb2\libc.a(lib_a-malloc.o)
                             
c:/progra~1/codesourcery/sourcery_codebench_lite_for_arm_eabi/bin/../lib/gcc/arm-none-eabi/4.7.3/../../../../arm-none-eabi/lib/thumb2\libc.a(lib_a-rand.o)
(malloc)
c:/progra~1/codesourcery/sourcery_codebench_lite_for_arm_eabi/bin/../lib/gcc/arm-none-eabi/4.7.3/../../../../arm-none-eabi/lib/thumb2\libc.a(lib_a-mallocr.o)
                             
c:/progra~1/codesourcery/sourcery_codebench_lite_for_arm_eabi/bin/../lib/gcc/arm-none-eabi/4.7.3/../../../../arm-none-eabi/lib/thumb2\libc.a(lib_a-malloc.o)
(_malloc_r)
c:/progra~1/codesourcery/sourcery_codebench_lite_for_arm_eabi/bin/../lib/gcc/arm-none-eabi/4.7.3/../../../../arm-none-eabi/lib/thumb2\libc.a(lib_a-mlock.o)
                             
c:/progra~1/codesourcery/sourcery_codebench_lite_for_arm_eabi/bin/../lib/gcc/arm-none-eabi/4.7.3/../../../../arm-none-eabi/lib/thumb2\libc.a(lib_a-mallocr.o)
(__malloc_lock)
c:/progra~1/codesourcery/sourcery_codebench_lite_for_arm_eabi/bin/../lib/gcc/arm-none-eabi/4.7.3/../../../../arm-none-eabi/lib/thumb2\libc.a(lib_a-sbrkr.o)
                             
c:/progra~1/codesourcery/sourcery_codebench_lite_for_arm_eabi/bin/../lib/gcc/arm-none-eabi/4.7.3/../../../../arm-none-eabi/lib/thumb2\libc.a(lib_a-mallocr.o)
(_sbrk_r)
c:/progra~1/codesourcery/sourcery_codebench_lite_for_arm_eabi/bin/../lib/gcc/arm-none-eabi/4.7.3/../../../../arm-none-eabi/lib/thumb2\libc.a(lib_a-freer.o)
                             
c:/progra~1/codesourcery/sourcery_codebench_lite_for_arm_eabi/bin/../lib/gcc/arm-none-eabi/4.7.3/../../../../arm-none-eabi/lib/thumb2\libc.a(lib_a-malloc.o)
(_free_r)
c:/progra~1/codesourcery/sourcery_codebench_lite_for_arm_eabi/bin/../lib/gcc/arm-none-eabi/4.7.3/../../../../arm-none-eabi/lib/thumb2\libc.a(lib_a-reent.o)
                             
c:/progra~1/codesourcery/sourcery_codebench_lite_for_arm_eabi/bin/../lib/gcc/arm-none-eabi/4.7.3/../../../../arm-none-eabi/lib/thumb2\libc.a(lib_a-sbrkr.o)
(errno)