malloc ld script requirements

Vitus Jensen
Wed Apr 28 18:56:00 GMT 2004

> Bryce Schober wrote:
> > What does the memory heap (malloc, etc) need from an ld script?


> I ask this question here because the anwer I got on the
> binutils-list was:
> > That entirely depends on how your implementation of malloc works.  It
> > might require you to define symbols in the linker script that it 
> > can refer
> > to later to know the amount of memory available.  Or your malloc
> > implementation might depend on something else in your BSP to test,
> > measure,
> > deduce or infer the amount of memory.  You'll have to find out
> > what library
> > code you're using and look at how it works.
> I really hope that you're not going to ask me to delve into the
> source to figure this out. Can a newbie get some help?

malloc() requires you to supply a sbrk() routine which is called whenever
malloc() needs more memory.  sbrk() is one of those ~17 routines you have to
implement in something called libgloss.

HOW you implement sbrk() is totally up to you.  See the libgloss
subdirectory for examples.  And -- sorry -- you have to delve into that


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