Make C floating point literals float (rather than double)

Question

It is well known that in C, floating point literals (e.g. 1.23) have type double. As a consequence, any calculation that involves them is promoted

Answer 1

The -Wunsuffixed-float-constants flag could be used too, maybe combined with some of the other options in the accepted answer above. However, this probably won't catch unsuffixed constants in system headers. Would need to use -Wsystem-headers to catch those too. Could generate a lot of warnings...