C++ to_string float

[HorstvanGrass]

I simply want to convert a float into a string or at least a char array. However I always get wrong returns. For example the length is over 150000 while I want to convert 3.3... For integer to_string works great. But not floating points.

string str=to_string(3.3f);

[tesc]

Hi,

How are you enabling C++ support in the project? What C++ libraries have you enabled? I am not sure if for instance the Minimal C++ Library supports to_string for floating point numbers.

Also, do you get any warnings when building the project?

Regards,
Terje

[HorstvanGrass]

This is my project conf file

CONFIG_LOG=y
CONFIG_STDOUT_CONSOLE=y
CONFIG_I2C=y
CONFIG_SENSOR=y
CONFIG_SENSOR_LOG_LEVEL_DBG=y
CONFIG_CBPRINTF_FP_SUPPORT=y

# Bluetooth LE
CONFIG_BT=y

CONFIG_BT_PERIPHERAL=y
CONFIG_BT_NUS=y
CONFIG_BT_DEVICE_NAME="MY_LBS1"
CONFIG_NEWLIB_LIBC_MIN_REQUIRED_HEAP_SIZE=2048
CONFIG_DEBUG_THREAD_INFO=y
CONFIG_NO_OPTIMIZATIONS=y

### C++ ###
CONFIG_LOG_BACKEND_UART=y

CONFIG_STD_CPP20=y
CONFIG_CPP_MAIN=y

CONFIG_CPLUSPLUS=y
CONFIG_LIB_CPLUSPLUS=y

The minimal c++ is not found by the following line

CONFIG_MINIMAL_LIBCPP=y

[HorstvanGrass]

Add

CONFIG_NEWLIB_LIBC=y CONFIG_NEWLIB_LIBC_NANO=n

to the project file, even if zephyr tells it is obsolete. Fix all bugs.