Dependency grr no longer building + removed from CRAN

[halhen]

The dependency grr has been removed from CRAN from issues not being corrected on time.

Trying to install grr in our recent builds on R4.6 gives the error message below. grr seems to be an inactive project, so there might not be much hope for it to be fixed upstream.

grr.cpp: In function ‘SEXPREC* sortcpp(SEXP)’:
grr.cpp:43:17: error: ‘STRING_PTR’ was not declared in this scope; did you mean ‘STRING_PTR_RO’?
   43 |       std::sort(STRING_PTR(x), STRING_PTR(x) + LENGTH(x), cmp_char);
      |                 ^~~~~~~~~~
      |                 STRING_PTR_RO
grr.cpp: In function ‘void internalOrder(int*, SEXP)’:
grr.cpp:116:20: error: ‘STRING_PTR’ was not declared in this scope; did you mean ‘STRING_PTR_RO’?
  116 |     SEXP* start = &STRING_PTR(x)[0];
      |                    ^~~~~~~~~~
      |                    STRING_PTR_RO
grr.cpp: In function ‘SEXPREC* matches(SEXP, SEXP)’:
grr.cpp:283:21: error: ‘STRING_PTR’ was not declared in this scope; did you mean ‘STRING_PTR_RO’?
  283 |     SEXP* astart = &STRING_PTR(a)[0];
      |                     ^~~~~~~~~~
      |                     STRING_PTR_RO

You might need to consider moving away from this dependency