Beginner for Nios2

1. Why I can't use redhat 9 for Building nios-linux?

could i upate the gcc for redhat 9?

2. about jffs2 's problems on uClinux 2.4.22.

We have 2MB SST39LV1601 flash and The flash partition is mounted as a jffs2 partition. When we try to remove and copy some files to and from the filesystem which is mounted as a root filesystem it occasionally gives the following warning:

(1) jffs2_read_inode(): No data nodes found for inode# 181.

then, this filesystem some files can't be accessed to and giving this warning when booting.

(2) sometimes it gives the following warning :

JFFS2: Erase block at 0x0008b000 is not formatted. It will be erased

.....

Because my application needs sending and receiving data realtime,it run seems normal,but it happens some delay and crash sometimes.

What are possible causes of that gives this warning?