I kept at it mostly as an exercise to test different compiler options. I found that a miner implemented in C runs in 1/5 the time of a Perl script (but at ~10 times more lines of code). Also, compiling with "-march=native" reduces the run time by ~10%, and concatenating all C files together to compile and link in a single step saves another ~0.5%.

I felt like I got enough out of this exercise and don't need to burn more CPU cycles on it :)