Use -O not -O3: reduces ccan/tdb test time from 24 to 18 seconds.
[ccan] / ccan / array / test /
drwxr-xr-x   ..
-rw-r--r-- 12541 lotsOfNumbers.h
-rw-r--r-- 804028 lotsOfStrings.h
-rw-r--r-- 9423 run.c
-rw-r--r-- 101544 testLits.h
-rw-r--r-- 3215 testLits.h.template
-rwxr-xr-x 1395 testLits_generate.pl