unable to install packages MacOS Big Sur

[Laurapetri]

hi there,

I can't install and load any packages since I updated my Mac to Big Sur.

 install.packages("readxl")
also installing the dependency ‘tibble’


  There is a binary version available but the source version is later:
       binary source needs_compilation
tibble  3.0.6  3.1.0              TRUE

Do you want to install from sources the package which needs compilation? (Yes/no/cancel) 
versuche URL 'https://cran.rstudio.com/bin/macosx/el-capitan/contrib/3.6/readxl_1.3.1.tgz'
Content type 'application/x-gzip' length 1646895 bytes (1.6 MB)
==================================================
downloaded 1.6 MB


The downloaded binary packages are in
	/var/folders/40/r3dq1_nn0t7cd3sl1rxwvlhm0000gn/T//RtmpSrFIYa/downloaded_packages
installing the source package ‘tibble’

versuche URL 'https://cran.rstudio.com/src/contrib/tibble_3.1.0.tar.gz'
Content type 'application/x-gzip' length 686464 bytes (670 KB)
==================================================
downloaded 670 KB

* installing *source* package ‘tibble’ ...
** Paket ‘tibble’ erfolgreich entpackt und MD5 Summen überprüft
** using staged installation
** libs
xcrun: error: invalid active developer path (/Library/Developer/CommandLineTools), missing xcrun at: /Library/Developer/CommandLineTools/usr/bin/xcrun
ERROR: compilation failed for package ‘tibble’
* removing ‘/Library/Frameworks/R.framework/Versions/3.6/Resources/library/tibble’
Warning in install.packages :
  installation of package ‘tibble’ had non-zero exit status

The downloaded source packages are in
	‘/private/var/folders/40/r3dq1_nn0t7cd3sl1rxwvlhm0000gn/T/RtmpSrFIYa/downloaded_packages’

I'd be happy for some help!

Best wishes
Laura

[andresrcs]

@Laurapetri

Do you want to install from sources the package which needs compilation? (Yes/no/cancel) 

The easiest solution would be to answer "no" to this question, you would get a precompiled binary version that is a little older but much easier to install.
If you need to install the latest version from source, then you need to install Xcode in your system (not in R) and the recommended development tools for macOS systems.
https://cran.r-project.org/bin/macosx/tools/

[Laurapetri]

Thank you for the fast answer! Answering no worked!
Do you know why this error occurred? I have the latest version of R.

[andresrcs]

Newer versions of packages are usually only available in source form when they just get published (binaries are added later) so they require compilation, and for compiling packages yourself you need the software I mentioned before.