编译不成功

在Centos7环境下编译Go1.4.3，在os/exec的测试阶段出现以下Pipe问题，请大虾帮忙解释一下问题原因，谢谢。

ok os 1.528s --- FAIL: TestPipeLookPathLeak (0.45s) exec_test.go:253: leaked 4 fds; want ~0; have: COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME exec.test 64225 root cwd DIR 8,3 4096 204974345 /home /dev/training/go/src/os/exec exec.test 64225 root rtd DIR 8,3 4096 128 / exec.test 64225 root txt REG 8,3 4795687 205262100 /tmp/ go-build674695459/os/exec/_test/exec.test exec.test 64225 root mem REG 8,3 2107760 135059827 /usr/ lib64/libc-2.17.so exec.test 64225 root mem REG 8,3 141616 135076269 /usr/ lib64/libpthread-2.17.so exec.test 64225 root mem REG 8,3 164336 135059820 /usr/ lib64/ld-2.17.so exec.test 64225 root 0r CHR 1,3 0t0 5701 /dev/ null exec.test 64225 root 1w FIFO 0,8 0t0 429830 pipe exec.test 64225 root 2w FIFO 0,8 0t0 429830 pipe exec.test 64225 root 3r CHR 1,3 0t0 5701 /dev/ null exec.test 64225 root 4r FIFO 0,8 0t0 430372 pipe exec.test 64225 root 5w FIFO 0,8 0t0 430372 pipe exec.test 64225 root 6r FIFO 0,8 0t0 430373 pipe exec.test 64225 root 7w FIFO 0,8 0t0 430373 pipe exec.test 64225 root 8r FIFO 0,8 0t0 430374 pipe

            originally:
            COMMAND     PID USER   FD   TYPE DEVICE SIZE/OFF      NODE NAME
            exec.test 64225 root  cwd    DIR    8,3     4096 204974345 /home                                                                                                                                   /dev/training/go/src/os/exec
            exec.test 64225 root  rtd    DIR    8,3     4096       128 /
            exec.test 64225 root  txt    REG    8,3  4795687 205262100 /tmp/                                                                                                                                   go-build674695459/os/exec/_test/exec.test
            exec.test 64225 root  mem    REG    8,3  2107760 135059827 /usr/                                                                                                                                   lib64/libc-2.17.so
            exec.test 64225 root  mem    REG    8,3   141616 135076269 /usr/                                                                                                                                   lib64/libpthread-2.17.so
            exec.test 64225 root  mem    REG    8,3   164336 135059820 /usr/                                                                                                                                   lib64/ld-2.17.so
            exec.test 64225 root    0r   CHR    1,3      0t0      5701 /dev/                                                                                                                                   null
            exec.test 64225 root    1w  FIFO    0,8      0t0    429830 pipe
            exec.test 64225 root    2w  FIFO    0,8      0t0    429830 pipe
            exec.test 64225 root    4r  FIFO    0,8      0t0    429876 pipe
            exec.test 64225 root    6r  FIFO    0,8      0t0    429877 pipe

FAIL FAIL os/exec 0.738s ok os/signal 4.332s ok os/user 0.004s