Arm Mbed OS support forum

Warning: 'sleep_for' is deprecated. What to use?

Hi all,

I have warning:
Warning: 'sleep_for' is deprecated: Pass a chrono duration, not an integer millisecond count. For example use 5srather than5000. [since mbed-os-6.0.0] [-Wdeprecated-declarations] in "main.cpp",

If I use Online Compiler :
it build with out warning.

but offline build GCC_ARM trow an error that it does not recognize ‘s’.

mbed-os is on versinion 6.x

Thanks for advices

I don’t know how about other revisions but with the gcc-arm-none-eabi-9-2019-q4-major the chrono literals like 5s work fine. And I expect it should be the same with newer revisions. Maybe you just left a space char between the number and the ‘s’ char, like 5 s. Since I use a code beautifier (which is not aware of those special literals) I also frequently have to fix such errors manually.

In mbed-os 6.x, you can resolve the warnings by including the following at the top of your source file after the #includes.

using namespace std;