Optimization levels with tiny C compiler

Question

I've read in the manpage that

Note: GCC options -Ox, -fx and -mx are ignored.

It produces different binary sizes, compiling st with gcc -O3, the binary size is 120K and with tcc it's 112K.

Is code compiled with tcc running slower than gcc -O3?

Answer 1

Tcc does not optimise. Normally, gcc's optimisations result in binaries which run considerably faster. (The size of the binary is not a predictor of execution speed, by the way.)