Thanks for your reply. Actually the MIPS system is from ARCA (www.arca.com.cn) and is set to singleuser mode, and I have found where the bug lies: the so call gcc-compliance compiler have made great mistakes:
I am porting the device driver from x86 arch i386 to MIPS arch arca (domestic CPU), where ARCA provide a gcc-like compiler, but there are much bugs in the compiler, where much should be done to improve it. Poor ARCA environment! Poor me!
They have their own MIPS compiler named arca2-xxx, you can see their web site for more information, but their compiler and linker are obvious of poor quality.