LCAO Gamma-only density matrix output does not have the correct precision

[jinzx10]

Describe the bug

I'm looking for the density matrices from some LCAO, Gamma-only calculations. When running with input option "out_dm 1", the matrix elements in the output file "SPIN1_DM" contain an insane number of digits (~20000) as shown below:

The output looks normal in v3.4.0 and the problem was introduced in v3.4.1.

Expected behavior

No response

To Reproduce

The problem seems to be general. For example, one can simply append the following to examples/scf/lcao_Si2/INPUT to reproduce the problem:

gamma_only 1
out_dm 1

Environment

No response

Additional Context

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