OK, this might be a very general question but I'm not to familiar with the topic and happy for any hint.
I have a Cross Compiling tool chain from SoucereyCodeBench for ARM ( arm-xilinx-linux-gnueabi-). I cross compiled a library which uses the compiler Options: -DSC_INCLUDE_FX -DSC_USE_PTHREADS -pthreads -fPIC -DPIC
So if I want to use the libary for bare metal program I would need pthreads for the bare metal compiler (arm-xilinx-eabi-) I guess?
Otherwise my program probally wouldn't run or compile in the first place. So could it be done to compile pthreads for bare metal?
I think it will be a matetr of porting your code rather than simply cross-compiling it unchanged. As its name suggests POSIX threads (pthreads) assumes a POSIX API.
If you need threads on a bare metal ARM target, the you at least need some sort of thread scheduling libraries of which there are many. Most RTOSs are not full OSs in the sense of Linux, but rather simple schedulers with IPC mechanisms that link as static libraries like any other to your monolithic application - that probably still counts as "bare metal" in the sense that the system boots directly to your main() function where you are responsible for creating tasks/threads and starting the scheduler.
Some RTOSs support POSIX APIs and therefore pthreads, but these tend to be the larger more complete OSs rather than simple schedulers - either way they are generally smaller and more scalable then Linux so may meet yout "bare metal" requirements nonetheless.
Of course nothing stops you from creating a wrapper around any RTOS library to provide a pthread compatible API that might make porting your code simpler.