链接时出错
(.text+0x400):undefined reference to '_aeabi_i2d'
(.text+0x400):undefined reference to '_aeabi_dmul'
(.text+0x400):undefined reference to '_aeabi_d2uiz'
(.text+0x400):undefined reference to '_aeabi_i2d'
(.text+0x400):undefined reference to '_aeabi_dmul'
(.text+0x400):undefined reference to '_aeabi_d2uiz'