Error(s) in re-building vignettes:
--- re-building ‘intro.Rmd’ using rmarkdown
dyld: lazy symbol binding failed: Symbol not found: ____chkstk_darwin
  Referenced from: /usr/local/bin/pandoc (which was built for Mac OS X 10.15)
  Expected in: /usr/lib/libSystem.B.dylib

dyld: Symbol not found: ____chkstk_darwin
  Referenced from: /usr/local/bin/pandoc (which was built for Mac OS X 10.15)
  Expected in: /usr/lib/libSystem.B.dylib

Error: processing vignette 'intro.Rmd' failed with diagnostics:
pandoc document conversion failed with error 6
--- failed re-building ‘intro.Rmd’

--- re-building ‘united_nations.Rmd’ using rmarkdown

Attaching package: 'dplyr'

The following objects are masked from 'package:stats':

    filter, lag

The following objects are masked from 'package:base':

    intersect, setdiff, setequal, union

If you use data from the unvotes package, please cite the following:

Erik Voeten "Data and Analyses of Voting in the UN General Assembly" Routledge Handbook of International Organization, edited by Bob Reinalda (published May 27, 2013)
Warning in countrycode(item2, "country.name", "iso2c") :
  Some values were not matched unambiguously: Czechoslovakia, German Democratic Republic, Yemen Arab Republic, Yemen People's Republic, Yugoslavia, Zanzibar


Attaching package: 'igraph'

The following objects are masked from 'package:dplyr':

    as_data_frame, groups, union

The following objects are masked from 'package:stats':

    decompose, spectrum

The following object is masked from 'package:base':

    union

Warning: `data_frame()` is deprecated, use `tibble()`.
This warning is displayed once per session.
Warning in countrycode(country, "country.name", "continent") :
  Some values were not matched unambiguously: Czechoslovakia, German Democratic Republic, Yemen Arab Republic, Yemen People's Republic

Using `stress` as default layout
dyld: lazy symbol binding failed: Symbol not found: ____chkstk_darwin
  Referenced from: /usr/local/bin/pandoc (which was built for Mac OS X 10.15)
  Expected in: /usr/lib/libSystem.B.dylib

dyld: Symbol not found: ____chkstk_darwin
  Referenced from: /usr/local/bin/pandoc (which was built for Mac OS X 10.15)
  Expected in: /usr/lib/libSystem.B.dylib

Error: processing vignette 'united_nations.Rmd' failed with diagnostics:
pandoc document conversion failed with error 6
--- failed re-building ‘united_nations.Rmd’

SUMMARY: processing the following files failed:
  ‘intro.Rmd’ ‘united_nations.Rmd’

Error: Vignette re-building failed.
Execution halted