User's Guide 6.2 says:
"So, when we want very fast code, we use: -O -fvia-C."
but I've seen programs which use the (apparently undocumented) -O2-for-C
flag too.
In fact, generally speaking anyone of:
-O -fvia-C
-O2 -fvia-C
-O -fvia-C -O2-for-C
-O2 -fvia-C -O2-for-C
produces different output... So, which is the best choice?
Juanma