I've managed to compile APR for the Texas Instruments c6x architecture.
However, I had to make a small modification to /locks/unix/thread_mutex.c:

at line 60, i've changed:

        rv = pthread_mutexattr_settype(&mattr, PTHREAD_MUTEX_RECURSIVE);


  rv = pthread_mutexattr_settype(&mattr, PTHREAD_MUTEX_RECURSIVE_NP);

Maybe this can be automated by specifying an extra define in case of c6x architecture?
I'm not really familiar enough to do this myself.


PS: Building APR was done by issueing:

ac_cv_file__dev_zero=yes ac_cv_func_setpgrp_void=yes apr_cv_process_shared_works=yes apr_cv_mutex_robust_shared=yes apr_cv_tcp_nodelay_with_cork=yes ac_cv_sizeof_struct_iovec=8 apr_cv_mutex_recursive=yes ./configure --host=c6x --prefix=$(pwd)/output CC=/opt/gcc-c6x/bin/c6x-uclinux-gcc AR=/opt/gcc-c6x/bin/c6x-uclinux-ar IDL_CPP=cpp ARFLAGS=rv CFLAGS=-lpthread --disable-ipv6

make && make install