How do I find the correct character after glibc- in sourceFileMap?

[markus-zhang]

Hi,
In launch.json I have the following config:

"sourceFileMap": {
            "/build/glibc-sMfBJT": "/opt/src/glibc-2.35"
       }

However stepping into glibc source code doesn't work. VSCode simply flashes by but does not step into glibc source. When I press F12 on, say, printf it does recognize and show the file. Then I realized that I pulled the whole repo, including the launch.json file, which was created from another laptop. So this is probably the reason VSCode refuses to step into library source code.

I have tried very hard to find the correct combination after /build/glibc- with no avail. Can someone tell me how to find it? Please do not point me to any GitHub issue as I have searched through perhaps most of them. This is also a clean VSCode install so there is no skipFile setting either.