参考：
08 调试利器GDB（下）https://www.cnblogs.com/lh03061238/p/13177510.html
使用GDB进行断点调试 https://www.cnblogs.com/-glb/p/12514577.html
breakpoint和watchpoint的区别 https://www.jianshu.com/p/9462a5280004
About breakpoints and watchpoints https://www.cnblogs.com/zjbfvfv/p/11949201.html
breakpoint和watchpoint/data breakpoint https://blog.csdn.net/gengshenghong/article/details/7404296
gdb 和 watchpoint http://www.kgdb.info/gdb_watchpoint/
Notes on Hardware Breakpoints and Watchpoints https://aarzilli.github.io/debugger-bibliography/hwbreak.html
gdb里的软件观察点 (software watchpoint) 和硬件观察点 (hardware watchpoint)区别 https://blog.csdn.net/geekster/article/details/6641099
gdb 系列(1) (hwbreakpoint\watchpoint) https://blog.csdn.net/green369258/article/details/55510650