NCS 3.4.0 - missing cbprintf

RE: NCS 3.4.0 - missing cbprintf

Achim Kraus — Tue, 18 Aug 2026 06:22:54 GMT

Anyway, thanks a lot for all your help.

I'm looking forward to "LTS", hope that reduces the time spended in migrations.

Achim Kraus — Tue, 18 Aug 2026 06:17:33 GMT

I'm just wondering, that such a change, which I consider a major one, seems to be not mentioned. Or do I miss something?

Amanda Hsieh — Mon, 17 Aug 2026 19:45:46 GMT

For current NCS with the bundled Zephyr SDK, it is effectively no longer supported as a practical option on the default toolchain.

Achim Kraus — Mon, 17 Aug 2026 17:43:33 GMT

Yes, that works.

According the lib/os/CMakeLists,txt, it should have been included with

```

if(NOT CONFIG_PICOLIBC)
zephyr_sources(cbprintf.c)
endif()

```

I'm used to NEWLIB_LIBC, but for reasons unknown by me, that seems to be not longer supported.

Checking the migration guides for nrf or zephyr I miss to read, that supporting NEWLIB_LIBC is discontinued.

So, is that a mistake or is NEWLIB_LIBC really not longer supported?

Amanda Hsieh — Mon, 17 Aug 2026 16:24:35 GMT

Hi Achim,

Could you try to add " target_sources(app PRIVATE ${ZEPHYR_BASE}/lib/os/cbprintf.c) " to the CMakeLists.txt to see whether it helps or not?

Regards,
Amanda H.