001、问题：configure: WARNING: expat is missing or unusable; some features may be unavailable.
002、解决方法
[root@PC1 gdb-13.2]# yum install expat-devel
003、验证：
参考：https://stackoverflow.com/questions/37352188/gdb-configure-script-cant-find-expat-is-there-a-way-to-specify-where-to-find-it