How to use malloc in nRF9160?

RE: How to use malloc in nRF9160?

robbsadler — Thu, 20 Mar 2025 17:28:59 GMT

Even now in 2025 in SDK 2.8, I was getting

undefined reference to `k_malloc`

The above suggestion was the solution. It would be helpful if this rule requiring heap space be allocated was mentioned in the compiler error instead of an undefined reference.

RE: How to use malloc in nRF9160?

drunot — Thu, 17 Sep 2020 11:28:16 GMT

Have you remembered to allocate heap space? E.g. set 'CONFIG_HEAP_MEM_POOL_SIZE' in 'prj.conf' to a non zero value?

RE: How to use malloc in nRF9160?

KevinThompson-SR — Sun, 30 Aug 2020 03:32:49 GMT

I'm having same exact issue... any resolution or suggestions?

RE: How to use malloc in nRF9160?

lavande — Wed, 26 Feb 2020 05:37:48 GMT

Hi , Martin,

Where is the definition of 'k_malloc'?

RE: How to use malloc in nRF9160?

TBP — Thu, 17 Oct 2019 15:16:12 GMT

Hey,

I tried using k_malloc and got a linking error:

undefined reference to `k_malloc`

Is there something else I need to in order to use k_malloc?

Thanks,

Tal

RE: How to use malloc in nRF9160?

Martin Lesund — Thu, 21 Mar 2019 08:49:00 GMT

Hello Yusuke,

I would recommend to check out the documentation.

You can use k_malloc();

Here is an example on how to allocate memory:

char *mem_ptr;

mem_ptr = k_malloc(200);
if (mem_ptr != NULL)) {
    memset(mem_ptr, 0, 200);
    ...
} else {
    printf("Memory not allocated");
}