Error(s) in re-building vignettes:
--- re-building ‘adp.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 'adp.Rmd' failed with diagnostics:
pandoc document conversion failed with error 6
--- failed re-building ‘adp.Rmd’

--- re-building ‘ctd.Rmd’ using rmarkdown
Loading required package: gsw
Loading required package: testthat
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 'ctd.Rmd' failed with diagnostics:
pandoc document conversion failed with error 6
--- failed re-building ‘ctd.Rmd’

--- re-building ‘flags.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 'flags.Rmd' failed with diagnostics:
pandoc document conversion failed with error 6
--- failed re-building ‘flags.Rmd’

--- re-building ‘map_projections.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 'map_projections.Rmd' failed with diagnostics:
pandoc document conversion failed with error 6
--- failed re-building ‘map_projections.Rmd’

--- re-building ‘oce.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 'oce.Rmd' failed with diagnostics:
pandoc document conversion failed with error 6
--- failed re-building ‘oce.Rmd’

--- re-building ‘subclassing.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 'subclassing.Rmd' failed with diagnostics:
pandoc document conversion failed with error 6
--- failed re-building ‘subclassing.Rmd’

SUMMARY: processing the following files failed:
  ‘adp.Rmd’ ‘ctd.Rmd’ ‘flags.Rmd’ ‘map_projections.Rmd’ ‘oce.Rmd’
  ‘subclassing.Rmd’

Error: Vignette re-building failed.
Execution halted