[Rd] R does not start on Fedora 34

[Gábor Csárdi]

Dear all,

Fedora 34 was released two days ago, and with a fresh build of R I get

[root using 2dba8b3587c1 R-devel]# bin/R
ERROR: R_HOME ('/tmp/R-devel') not found

on it, coming from
https://github.com/wch/r-source/blob/0f0092adf14b8bd17bcce1cac0ee26b928355dab/src/scripts/R.sh.in#L263

Apparently `test -x` returns 1 for an existing 755 directory on Fedora 34:
❯ docker run -ti fedora:latest
[root using f944f25b16b4 /]# test -x /tmp/
[root using f944f25b16b4 /]# echo $?
1

On Fedora 33 this was different:
❯ docker run -ti fedora:33
[root using ea55a1b92215 /]# test -x /tmp/
[root using ea55a1b92215 /]# echo $?
0

A workaround would be to use `test -d` which still return 0 on Fedora 34.

FYI,
Gabor