Printf float setting in mbed-app.json ignored

[wvdvegt]

In the mbed-app.json one had/has to add the line:

platform.minimal-printf-enable-floating-point": 1

in order to force the mbed-os to include float support for *printf() statements when building outside platformio (if ommitted the placeholders as %f are output).

However adding this to the mbed-app.json in a platformio mbed-os6 project does not create code that handles floats in *printf() statements.

I had to add the line:

build_flags = -Wl,-u,_printf_float,-u,_scanf_float

to the platformio.ini file as well.