undefined reference to 'end' with nRF Connect SDK v2.4.0

RE: undefined reference to 'end' with nRF Connect SDK v2.4.0

ske — Tue, 11 Jul 2023 06:54:19 GMT

Hello,

We enabled the CONFIG_DEBUG=y in prj.conf and linker error is resolved with nRF connect sdk v2.4.0.

We surprised with this and want to understand about this dynamic memory allocation support removed in nRF Connect SDK v2.4.0. Could you tell the reason behind ?

In our library, we have some requirements to use dynamic memory allocation instead of static allocation where will get the dynamic data in TF-M secure environment. Do you have any reference or any other way on this?

RE: undefined reference to 'end' with nRF Connect SDK v2.4.0

Øivind — Mon, 10 Jul 2023 15:32:19 GMT

I looked a bit more into it, and in order to use malloc heap must be enabled, and it is by default disabled in TF-M. In TF-M the heap is hardcoded to a small size of 0x200 and is only meant for debug builds.

CONFIG_DEBUG=y enables the heap and will likely remove the error, but I suggest managing the memory in some other way instead.

RE: undefined reference to 'end' with nRF Connect SDK v2.4.0

ske — Mon, 10 Jul 2023 11:43:36 GMT

Hello,

As you mentioned, we added the CONFIG_MINIMAL_LIBC=y in prj.conf and observed the same linker error. Then, we tried with CONFIG_NEWLIB_LIBC=y. This also providing the same linker error.

Could you please tell if any configuration needs to be enabled along with this?

RE: undefined reference to 'end' with nRF Connect SDK v2.4.0

Øivind — Mon, 10 Jul 2023 10:42:11 GMT

Hi,

Could you try to add CONFIG_MINIMAL_LIBC=y to prj.conf? If that doesn't work, can you try with CONFIG_NEWLIB_LIBC=y instead?