Xcode won't accept my password after a successful Swift build

I use Xcode 9.4.1 under MacOS 10.13.6. When I successfully build a Swift project, it asks for a password. In the past, I just typed my login password, but today that stopped working (Xcode merely creates another dialog window). I can login fine, so it's not the password. I checked that the Caps Lock key isn't on and I asked for help,

which took me to KeyChain Access. I located the login keychain but I don't know what the proper key is ("access", "codesign", and other terms mentioned in the dialog aren't there but there are two related to Xcode itself). Frankly

I would would just as soon give Xcode access without this check; the machine is my personal laptop and there is no issue with anyone else having access to my code. Any suggestions?

Larry


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