How do I find out why g++ takes a very long time on a particular file?

Question

I am building a lot of auto-generated code, including one particularly large file (~15K lines), using a mingw32 cross compiler on linux. Most files are extremely quick, but thi

Answer 1

It most probably includes TONNES of includes. I believe -MD will list out all the include files in a given CPP file (That includes includes of includes and so forth).