Unable to compile Nvidia Flex on Ubuntu

Question

I'm trying to compile Flex on Linux (Ubuntu 14.04). I'm getting the following error that I haven't been able to wrap my head around:

/usr/bin/ld: ../../../external/SDL2-2.0.4/lib/x64//libSDL2.a(SDL_syssem.o): undefined reference to symbol 'sem_getvalue@@GLIBC_2.2.5'
//lib/x86_64-linux-gnu/libpthread.so.0: error adding symbols: DSO missing from command line
collect2: error: ld returned 1 exit status

I have CUDA 7.5 installed with one of the latest NVIDIA drivers. Would appreciate your comments on how I should solve the issue.

Answer 1

I simply downloaded Flex v1.2 and it complied with no issues.