MinGW "make" starts very slowly

Question

After some pain and suffering, i managed to install everything necessary for MinGW to work on a computer not on the network.

It worked nicely for a couple days, but now I'm experiencing very long delays before anything starts to happen after i give the "make" command to build my project.

I tried disabling the network, as suggested here: Why is MinGW very slow? But it didn't help.

Note that it's not the actual compilation / linking progress that is slow, but the startup of those processes seems to take forever. 5-10 minutes. Except if i just did it, then it starts in 10-30 seconds.

I know, it used to take a lot longer to load those tapes on Commodore, but over the years I have grown impatient.

Any ideas?

Answer 1

Try doing make -r (without implicit rules). For me it was a difference between 30 seconds and fraction of a second for single cpp file.

Explanation:

I've had the same problem MinGW make long ago. I've used make -d to investigate. It was then obvious that make uses a gazillion of implicit rules for every dependency file - if my file had dep on shared_ptr.hpp then make checked for shared_ptr.hpp(o|c|cc|v|f|r|.. and dozens other combinations). Of course those files didn't exist. It looks like checking for file mod time/existence (when it doesn't really exist) on Windows platform is a lot slower than on Linux (becouse with Linux i didn't see any difference with/without -r switch).