This doesn't quite work, but it certainly points to the problem. See the following efforts. The problem seems to be due to libclang-dev or some of its pieces. How do I fix this? Should I remove libclang-dev and reinstall it? I don't want to break things worse trying to fix it.
rry@larry-VirtualBox:~/Downloads$ sudo gdebi rstudio-1.4.1717-amd64.deb
Reading package lists... Done
Building dependency tree
Reading state information... Done
Reading state information... Done
This package is uninstallable
Cannot install 'libclang-dev'
larry@larry-VirtualBox:~/Downloads$ sudo apt install libclang-dev
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:
The following packages have unmet dependencies:
libclang-dev : Depends: libclang-10-dev (>= 10~) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.
larry@larry-VirtualBox:~/Downloads$ sudo apt install libclang-10-dev
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:
The following packages have unmet dependencies:
libclang-10-dev : Depends: libclang-common-10-dev (= 1:10.0.0-4ubuntu1) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.
larry@larry-VirtualBox:~/Downloads$ sudo apt install libclang-common-10-dev
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:
The following packages have unmet dependencies:
libclang-common-10-dev : Depends: lib32gcc-s1 (>= 4.2) but it is not going to be installed
Depends: lib32stdc++6 (>= 4.1.1) but it is not going to be installed
Depends: libc6-i386 (>= 2.17) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.