rhel 5.9 doesn't compile (librados only) due to blkid error
Changes introduced in configure.ac check for blkid functions which don't exist on rhel 5.9. off master the configure executes, but on compilation:
common/blkdev.cc: In function 'int block_device_discard(int, int64_t, int64_t)':
common/blkdev.cc:177:20: error: 'BLKDISCARD' was not declared in this scope
return ioctl(fd, BLKDISCARD, range);
common/blkdev.cc:178:1: warning: control reaches end of non-void function [-Wreturn-type]
I've created a simple fix which put blkid work into RBD build scope.