g++: error: unrecognized command line option '-mt'

Question

I'm trying to compile a program from source. In an OpenSuse 12.1 chroot the program compiles fines, but in an OpenSuse leap 42.1 chroot I get the following error:

g++: error: unrecognized command line option '-mt'

I've searched (both on here and on google) but couldn't find much information on the -mt flag. What is this '-mt' flag?

Answer 1

This flag is used to compile and link multi-threaded applications.

With gcc you should use -pthread for both compiling and linking, no -lpthread is necessary.

When compiling -pthread sets the necessary macros, when linking it links in the required libraries.