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

I'd use #if 0 / #endif to eliminate large portions of the source file from compilation. Repeat with different blocks of code until you pinpoint which block(s) are slow. For starters, you can see if your #include's are the problem by using #if 0 / #endif to exclude everything but the #include's.