buildroot 出现 libc.so.0 => not found

Question

用buildroot-2011.2 和 buildroot-2009.11
编译完之后
交叉工具链不能使用（编译成静态的可用，态动不可用）提示找不到LIBC，但是在工具链下面有这个东西

$ mipsel-linux-gcc --version
mipsel-linux-gcc (GCC) 4.4.2
Copyright (C) 2009 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

$ mipsel-linux-gcc -v
Using built-in specs.
Target: mipsel-linux-uclibc
Configured with: /home/loongson/buildroot/buildroot-2009.11/output/toolchain/gcc-4.4.2/configure --prefix=/usr --build=i386-pc-linux-gnu --host=i386-pc-linux-gnu --target=mipsel-linux-uclibc --enable-languages=c --with-sysroot=/opt/gcc-cross-loongson --with-build-time-tools=/opt/gcc-cross-loongson/usr/mipsel-linux-uclibc/bin --disable-__cxa_atexit --enable-target-optspace --with-gnu-ld --disable-libssp --disable-tls --disable-shared --with-gmp=/home/loongson/buildroot/buildroot-2009.11/output/toolchain/gmp --with-mpfr=/home/loongson/buildroot/buildroot-2009.11/output/toolchain/mpfr --disable-nls --enable-threads --disable-multilib --disable-decimal-float --with-float=soft --with-abi=32 --with-tune=mips1
Thread model: posix
gcc version 4.4.2 (GCC)

$ file ./a.out
./a.out: ELF 32-bit LSB executable, MIPS, MIPS-I version 1 (SYSV), dynamically linked (uses shared libs), with unknown capability 0xf41 = 0x756e6700, not stripped

$ mipsel-linux-ldd ./a.out
        libc.so.0 => not found (0x00000000)
        /lib/ld-uClibc.so.0 => /lib/ld-uClibc.so.0 (0x00000000)