_sbrk_ and the sequence of requirements

Oct 17, 2006 2 Replies

Hi,



I am using Coldfire (MCF5272) and M68k Tool-chain.



_sbrk_ is a low level system call called by malloc. I got "undefined reference " for sbrk which is actually defined in libc . So, i tried including libc. ( I got the above info after some google searches for the _sbrk_ problem)



But, Libc is looking for some kind of functions present in libgloss.



I included libgloss.



After some searches i found the libgloss sourcecode inside newlib package which I compiled with --target = m68K. (Compilation took long time - takes 40 minutes and breaks finally (some kind of pointer problem) ). I did not get any readily available package that i can use it.



I need to find out the libgloss now for fixing this.



Tried to search in cygwin, they have one kind of libgloss for another archetecture. I would like to have libgloss for M68K. (MCF5272 Coldfire) which could solve the above problems . But, i am unable to get it. Could someone of you here share some info regarding the above problems that i face now.



Thx in advans, Karthik Balaguru



Are you perchance trying to adapt my nmalloc to your system (which should be possible). If so sbrk is defined in the (non-standard) unistd.h header. If not, you might want to take a look at it anyhow:

The nm utility may be of help in your search. In binutils.

Chuck F (cbfalconer at maineline dot net) Available for consulting/temporary embedded and systems.

Hi,

The newlib-1.14.0 got compiled well to generate the libgloss (It took

50 minutes for compilation ... pretty looooong) . I got the m68k along with the required m5200 stuffs which had all the necessary objects. . I did link with libnosys.a for resolving the sbrk's other reference requirements.

Now, i find that lot of errors oriented with _exit, _read and _sbrk have got resolved after using these libraries.

Thx , Karthik Balaguru

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