What does the gcc -R parameter do?

Question

I am trying to run an autotools configure script for the bson-cpp project, and it fails because it cannot determine what flags it needs to compile with boost_filesystem. A q

Answer 1

It is not a valid option for GCC, so it does not do anything.

It is possibly a valid option for other compilers though, which could be why autoconf gives it a shot.

Not all errors in the config.log files are a problem. autoconf figures out a lot of things by "guessing", i.e. trying something and keeping that if it worked.