Hello isbelen, Kindly look into the post I made earlier of enabling "--enable-pthreads" while configuring the SystemC library. Currently the Cygwin 64-bit SystemC library build is non-functional with Quick Threads Library for user space threading. Also, kindly refer the post discussing the same from Mr. @Philipp A Hartmann and Mr. @ralph.goergen. Regards, Ameya Vikram Singh