Hi Ernesto- If you are not using FreeRTOS ignore this.
If you are: Perhaps you have not got a correct sbrk setup.
Many FreeRTOS demos from NXP and ST have this problem.
See https://nadler.com/embedded/NXP_newlibAndFreeRTOS.html
Hope that helps!
Best Regards, Dave

On 5/3/2024 1:04 PM, Ernesto Vigano' wrote:
> It's a copy-paste error.
> The syntax is the right one
>
> Il ven 3 mag 2024, 09:22 Christophe Lyon <christophe.lyon@arm.com> ha 
> scritto:
>
>     Hi,
>
>     On 5/3/24 08:11, Ernesto Vigano' wrote:
>     > I need to use sprintf with floating point numbers (%f format
>     specifier)
>     > in a project based on rpmsg_lite_str_echo_rtos on the cortex-M (NXP
>     > Processor).
>     > I use the recommended
>     > arm-gnu-toolchain-12.3.rel1-mingw-w64-i686-arm-none-eabi
>     > I see that when I call
>     >
>     > sprintf(str, "%d" 3);
>     >
>     > the number 3 is printed to the string str.
>     >
>     > But if I have a floating point number and I use "%f" format
>     specifier
>     >
>     > sprintf(str, "%f" 3.5);
>
>     Is this a copy/paste error, or did you forget the ',' before the
>     number
>     you want to print?
>
>     Thanks,
>     Christophe
>
>     >
>     > I get
>     > ASSERT ERROR " Balloc succeeded ": file
>     >
>     "/data/jenkins/workspace/GNU-toolchain/arm-12/src/newlib-cygwin/newlib/libc/stdlib/mprec.c"
>     Line "783" function name ""
>     >
>     > It seems similar to this error
>     > forum.pjrc.com/index.php <http://forum.pjrc.com/index.php>
>     >
>     <https://forum.pjrc.com/index.php?threads/strange-compiling-problem-assertion-balloc-succeeded-failed-file-data-jenkins-w.72798/>
>     > that points to this fix
>     > github.com/.../f88aece242178ff0c187d56e34a79645fbc44a23
>     <http://github.com/.../f88aece242178ff0c187d56e34a79645fbc44a23>
>     >
>     <https://github.com/zephyrproject-rtos/newlib-cygwin/commit/f88aece242178ff0c187d56e34a79645fbc44a23>
>     >
>     > Is there a way to have sprintf working with floating point numbers?
>     >
>     > Thanks
>
-- 
Dave Nadler, USA East Coast voice (978) 263-0097,drn@nadler.com, Skype
  Dave.Nadler1