Bug Report

tsc won't compile newly added references in watch mode, while it compiles on initial start

I don't know if this description is clear :(
so i put an demonstration image in Steps to reproduce section

🔎 Search Terms

is:issue is:open references

🕗 Version & Regression Information

Typescript version : 4.5.5

⏯ Github repo

https://github.com/ryanroe/tsc-references-bug

💻 Steps to reproduce

1. clone the repo

git clone https://github.com/ryanroe/tsc-references-bug
cd tsc-references-bug
npm install
npx tsc --build ./tsconfig.json -w

2. open with Visual Studio Code (or any other editors) and remove the references field of root tsconfig.json
3. save
4. undo last operation (restore the references field)

🙁 Actual behavior

tsc says the compilation is successful

Found 0 errors. Watching for file changes

🙂 Expected behavior

tsc should complain about the error of referenced project as initial start

error TS2304: Cannot find name 'a'.

BUT when i removed the files field of root tsconfig.json , everything works!