When I first played around compiling the linux kernel, I found that most of it is like a suburban garage, with a kayak and a brake bleeder and a hoe and golf clubs.

Except the kernel puts the suburban garage to shame.

My kernel config shows:

  CONFIG_HAMRADIO=y
  CONFIG_BAYCOM_SER_FDX=m  (from AX.25 network device drivers)
  CONFIG_CAN_SJA1000=m  (from CAN device drivers)
  CONFIG_NFC_MRVL=m    (from Near Field Communication (NFC) devices)

after a while I just scroll faster and faster zooming past:

  CONFIG_VMWARE_BALLOON=m
  CONFIG_HABANA_AI=m
  CONFIG_MACINTOSH_DRIVERS=y
  CONFIG_HAPPYMEAL=m

...and loadable module support for 4 heart rate monitors, 18 inertial measurement units and 18 magnetometer sensors. Even 2 VME bridge drivers.

There are 11,018 lines of this.

So when he talked about compile time optimization, this is what I thought of.