Strange problems with gdbp arrays

The gdbp array encountered a strange problem-General Linux technology-Linux programming and kernel information. The following is a detailed description. Write a static array in C language:

Char s [10];

Then debug with gdb and use the p s command to display the array content, which is strange:

The array length is 10 and the element number should be 0-9. Why does gdb display only nine elements?
I used the x/11cb $1 Command to display the memory, and found that the tenth element seems to be in ......

Why does gdb do this?

Thank you for your help!