At 03:22 27-08-05 +0200, you wrote: >nobo...@web.de wrote: >> in the stackcheck example &_end is used for the stack check >> and the comment says that _end is defined by the linker. >> Because the heap begins behind the bss segment and grows >> towards the stack this seem to mean that stackcheck can only work >> if the heap is unused. >> Is this right? > >yes > > >if you have a heap (use of malloc/free) then the stack check has to be >done differently. one solution is to preclaculate a lowest allowed >address and put the stackmarker there: > > extern unsigned short __stack; > unsigned short *address = (unsigned short *)(__stack-50); >
Or write a small wrapper around malloc which determines which address is still available for the stack. Nico Coesel
