Error(s) in re-building vignettes:
--- re-building ‘howto.Rmd’ using rmarkdown
Warning in engine$weave(file, quiet = quiet, encoding = enc) :
  Pandoc (>= 1.12.3) not available. Falling back to R Markdown v1.
No protocol specified

(R:22436): GLib-GObject-WARNING **: invalid (NULL) pointer instance

(R:22436): GLib-GObject-CRITICAL **: g_signal_connect_data: assertion `G_TYPE_CHECK_INSTANCE (instance)' failed

(R:22436): Gtk-WARNING **: Screen for GtkWindow not set; you must always set
a screen for a GtkWindow before using the window

(R:22436): Gdk-CRITICAL **: gdk_screen_get_default_colormap: assertion `GDK_IS_SCREEN (screen)' failed

(R:22436): Gdk-CRITICAL **: gdk_colormap_get_visual: assertion `GDK_IS_COLORMAP (colormap)' failed

(R:22436): Gdk-CRITICAL **: gdk_screen_get_default_colormap: assertion `GDK_IS_SCREEN (screen)' failed

(R:22436): Gdk-CRITICAL **: gdk_screen_get_root_window: assertion `GDK_IS_SCREEN (screen)' failed

(R:22436): Gdk-CRITICAL **: gdk_screen_get_root_window: assertion `GDK_IS_SCREEN (screen)' failed

(R:22436): Gdk-CRITICAL **: gdk_window_new: assertion `GDK_IS_WINDOW (parent)' failed

 *** caught segfault ***
address 0x18, cause 'memory not mapped'

Traceback:
 1: .RGtkCall("S_gtk_widget_show_all", object, PACKAGE = "RGtk2")
 2: method(obj, ...)
 3: INIRENA$showAll()
 4: sara4r()
 5: eval(expr, envir, enclos)
 6: eval(expr, envir, enclos)
 7: withVisible(eval(expr, envir, enclos))
 8: withCallingHandlers(withVisible(eval(expr, envir, enclos)), warning = wHandler,     error = eHandler, message = mHandler)
 9: handle(ev <- withCallingHandlers(withVisible(eval(expr, envir,     enclos)), warning = wHandler, error = eHandler, message = mHandler))
10: timing_fn(handle(ev <- withCallingHandlers(withVisible(eval(expr,     envir, enclos)), warning = wHandler, error = eHandler, message = mHandler)))
11: evaluate_call(expr, parsed$src[[i]], envir = envir, enclos = enclos,     debug = debug, last = i == length(out), use_try = stop_on_error !=         2L, keep_warning = keep_warning, keep_message = keep_message,     output_handler = output_handler, include_timing = include_timing)
12: evaluate::evaluate(...)
13: evaluate(code, envir = env, new_device = FALSE, keep_warning = !isFALSE(options$warning),     keep_message = !isFALSE(options$message), stop_on_error = if (is.numeric(options$error)) options$error else {        if (options$error && options$include)             0L        else 2L    }, output_handler = knit_handlers(options$render, options))
14: in_dir(input_dir(), evaluate(code, envir = env, new_device = FALSE,     keep_warning = !isFALSE(options$warning), keep_message = !isFALSE(options$message),     stop_on_error = if (is.numeric(options$error)) options$error else {        if (options$error && options$include)             0L        else 2L    }, output_handler = knit_handlers(options$render, options)))
15: eng_r(options)
16: block_exec(params)
17: call_block(x)
18: process_group.block(group)
19: process_group(group)
20: withCallingHandlers(if (tangle) process_tangle(group) else process_group(group),     error = function(e) {        setwd(wd)        cat(res, sep = "\n", file = output %n% "")        message("Quitting from lines ", paste(current_lines(i),             collapse = "-"), " (", knit_concord$get("infile"),             ") ")    })
21: process_file(text, output)
22: knit(input, text = text, envir = envir, quiet = quiet)
23: (if (grepl("\\.[Rr]md$", file)) knit2html else if (grepl("\\.[Rr]rst$",     file)) knit2pandoc else knit)(file, encoding = encoding,     quiet = quiet, envir = globalenv(), ...)
24: vweave(...)
25: engine$weave(file, quiet = quiet, encoding = enc)
26: doTryCatch(return(expr), name, parentenv, handler)
27: tryCatchOne(expr, names, parentenv, handlers[[1L]])
28: tryCatchList(expr, classes, parentenv, handlers)
29: tryCatch({    engine$weave(file, quiet = quiet, encoding = enc)    setwd(startdir)    output <- find_vignette_product(name, by = "weave", engine = engine)    if (!have.makefile && vignette_is_tex(output)) {        texi2pdf(file = output, clean = FALSE, quiet = quiet)        output <- find_vignette_product(name, by = "texi2pdf",             engine = engine)    }    outputs <- c(outputs, output)}, error = function(e) {    thisOK <<- FALSE    fails <<- c(fails, file)    message(gettextf("Error: processing vignette '%s' failed with diagnostics:\n%s",         file, conditionMessage(e)))})
30: tools:::buildVignettes(dir = "/Volumes/SSD-Data/Builds/R-dev-web/QA/Simon/packages/el-capitan-x86_64/results/3.6/sara4r.Rcheck/vign_test/sara4r",     ser_elibs = "/tmp/Rtmp9KxCjV/file56ab1fb075ba.rds")
An irrecoverable exception occurred. R is aborting now ...