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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

SUMMARY: processing the following files failed:
  ‘about_keras_layers.Rmd’ ‘about_keras_models.Rmd’ ‘applications.Rmd’
  ‘backend.Rmd’ ‘custom_layers.Rmd’ ‘custom_models.Rmd’
  ‘custom_wrappers.Rmd’ ‘eager_guide.Rmd’ ‘faq.Rmd’
  ‘functional_api.Rmd’ ‘getting_started.Rmd’ ‘guide_keras.Rmd’
  ‘saving_serializing.Rmd’ ‘sequential_model.Rmd’
  ‘training_callbacks.Rmd’ ‘training_visualization.Rmd’
  ‘tutorial_basic_classification.Rmd’ ‘tutorial_basic_regression.Rmd’
  ‘tutorial_basic_text_classification.Rmd’
  ‘tutorial_overfit_underfit.Rmd’ ‘tutorial_save_and_restore.Rmd’
  ‘why_use_keras.Rmd’

Error: Vignette re-building failed.
Execution halted