obsolete LaTeX software in "R CMD check" on Mac?

Hello, All:


  ????? Might "R CMD check" on Mac use obsolete LaTeX software?


  ????? I ask, because "R CMD check" on my Mac started reporting LaTeX
errors on *.Rd files that previously passed "R CMD check" without
problems.? Dirk Eddelbuettel recommended I ask tex.stackexchange about
that.? I did that and got the following:

  ??? ??????? * "In a current tex system \textasciigrave should work with
your families - they don't have the glyph but latex will fall back
without error. In older systems it could give an error."


See:


https://tex.stackexchange.com/questions/543783/package-textcomp-error-symbol-textasciigrave-not-provided


  ????? Comments?
  ????? Thanks,
  ????? Spencer Graves


p.s.? An earlier post on this issue to r-pkg-devel is copied below.


-------- Forwarded Message --------
Subject: 	[R-pkg-devel] Error: Symbol \textasciigrave not provided by
(textcomp)
Date: 	Sun, 16 Feb 2020 14:21:17 -0600
From: 	Spencer Graves <spencer.graves at effectivedefense.org>
To: 	r-package-devel at r-project.org



Hello, All:


  ????? "R CMD check Ecfun_0.2-4.tar.gz" ends with 8 repetitions of the
following:


! Package textcomp Error: Symbol \textasciigrave not provided by
(textcomp)??????????????? font family zi4 in TS1 encoding.
(textcomp)??????????????? Default family used instead.

See the textcomp package documentation for explanation.
* checking PDF version of manual without hyperrefs or index ... ERROR
* DONE


  ????? This is using R 3.6.2 under macOS 10.15.3 applied to the current
development version of "https://github.com/sbgraves237/Ecfun".? Travis
CI reported that the build passed;? see
"https://travis-ci.org/sbgraves237/Ecfun/builds/650505913?utm_medium=notification&utm_source=email".



  ????? This looks to me like it's complaining about the use of the back
tick character ("`", below "~" on the top left key on a standard
American English keyboard), which I assume is equivalent to
"\textasciigrave" in certain contexts.


  ????? Six out of those 8 repetitions occur in the examples sections of
files "grepNonStandardCharacters.Rd", "subNonStandardCharacters.Rd", and
"subNonStandardNames.Rd". Those functions were written to fix parsing
errors with names like "Ra?l" that had been mangled by different
software before I could get it into R.


  ????? After a day's work failed to produce a work around, I decided to
ask this group.


  ????? What do you suggest?
  ????? Thanks,
  ????? Spencer Graves