编译线程---要加 -ldl -lpthread 参数

/opt/OpenWrt-Toolchain-ramips-for-mipsel_24kec+dsp-gcc-4.8-linaro_uClibc-0.9.33.2/toolchain-mipsel_24kec+dsp_gcc-4.8-linaro_uClibc-0.9.33.2/bin/mipsel-openwrt-linux-gcc -ldl -lpthread helloworld.c -o helloworld

export STAGING_DIR=/opt/wrtnode/staging_dir