make coverage-html would fail within build directory separate from source tree

Hi, hackers

During installation from source code, I created a build directory separate from the source tree, and execute the following command in the build directory:
/home/postgres/postgresql-13.2/configure -- enable-coverage
make
make check
make coverage-html

However, while executing make coverage-html, it failed with the following error messages:
/bin/lcov --gcov-tool /bin/gcov -q --no-external -c -i -d . -d /home/postgres/postgresql-13.2/ -o lcve_base.info
...
geninfo: ERROR: no .gcno files found in /home/postgres/postgresql-13.2/!
make: *** [lcov_base.info] Error 255
make: *** Deleting file 'lcov_base.info'

if I repeat the above steps within the source tree directory, make coverage-html works fine. From the official documentation, I didn't find any limitations for "make coverage-html", not sure if I miss something.

thanks
walker