关于R5F10PGG出现E0562320:Section address overflowed out of range : ".const"问题

This FAQ may help you:
FAQ - E0562320 Error Message (RL78 CC-RL)
https://en-support.renesas.com/knowledgeBase/16978833

上方连接的方法试过后，没有解决问题

.const should be located within mirror area.
Too big .text may cause this problem if exceed 0xb000. I suppose you should move .const in lower address than .text, or just move start address of data sections with far ROM option.

.const should be located within mirror area.
Too big .text may cause this problem if exceed 0xb000. I suppose you should move .const in lower address than .text, or just move start address of data sections with far ROM option.

还有一个问题想请教一下，程序相同并且没有错误但是起始地址不同的两个BOOT程序，同时烧录到FLASH，为什么从0x0000跳转到0x8000的BOOT程序后不能运行呢？

Then you should use -far_rom option or add __far for all const variables.
Once try downgrading E0562320 to warning with -CHange_message option to see how the sections are overwrapped in map file.