topic Re: undefined reference to __errno in i.MX RT Crossover MCUs

undefined reference to __errno

_bjs — Tue, 19 Jul 2022 12:54:31 GMT

Hello Please help:

I Added -(l)m for functions as roundf, fmaxf,
Now i am getting the following error:

I am not good with these side programming problems. What do i do to solve this?

I have added the following, this did not help:

#include "errno.h"

#define errno (*__error())
extern int * __error(void);

MCU linker is invoking:
arm-none-eabi-gcc -nostdlib -L"C:\Users\...

I am not familiar with what correct invoking is, arm-none-eabi-gcc I have seen before.

Is there some work around, adding some small-math-lib or something from github, anyone know?

Re: undefined reference to __errno

jingpan — Wed, 27 Jul 2022 06:48:32 GMT

Hi @_bjs ,

Can you give example code?

Regards,

Jing

Re: undefined reference to __errno

_bjs — Wed, 27 Jul 2022 10:53:39 GMT

I have solved this problem by moving from Redlib to Newlib.
The problem is difficult to create, on example projects i do not get the __errno issue.
Only on my final project, but i cannot share this easily.