Undefined : "__HEAP_START" Undefined : "__mem_limit" Undefined : "__stack_safety" link failed

[changxychang]

I am using Code Warrior 7.2 and building for the  54418 CPU, with MQX V3.7

I have ported some existing code over and fixed a bunch of compile errors. I am now stuck on some linker errors. I realise because the code uses malloc() and free() I need to define a heap.

Error   : Undefined : "__HEAP_START"

Referenced from "__break" in

Error   : Undefined : "__mem_limit"

alloc.c line 176   Referenced from "brk" in

Error   : Undefined : "__stack_safety"

alloc.c line 176   Referenced from "brk" in

Link failed.

I have no idea how to fix the problem with  "__mem_limit"  and "__stack_safety" variables

I have now removed all my app code and get the same link error.

I have tested a new project piece of code from MQX 3.7

Just adding the lines

#include <stdlib.h>

char *ptr;

ptr = malloc(1000)

triggers the link errors, Take out the malloc line, and link error goes away

I would appreciate any help on this problem, thanks.

[BielikM · Accepted solution]

Hi changxychang,

STDLIB is not part of MQX. MQX has own API for standard functions ( check MQX reference manual for that).

In your case use _mem_alloc(...) instead malloc(...).

Regards,

Martin