R包igraph无法安装，rstanarm需要.没有找到gfortran

Question

Rstanarm似乎安装正常。但尝试加载：

> library(rstanarm)
Error: package or namespace load failed for ‘rstanarm’ in loadNamespace(j <- i[[1L]], c(lib.loc, .libPaths()), versionCheck = vI[[j]]):
there is no package called ‘igraph’
In addition: Warning message:
package ‘rstanarm’ was built under R version 4.0.5 

在尝试安装igraph时，我收到了一条很长的文本，结尾是：

compilation terminated.
make: *** [C:/PROGRA~1/R/R-40~1.4/etc/i386/Makeconf:222: core/community/optimal_modularity.o] Error 1
ERROR: compilation failed for package 'igraph'
* removing 'C:/Users/siegl/OneDrive/Documents/R/win-library/4.0/igraph'
Warning in install.packages :
installation of package ‘igraph’ had non-zero exit status

旧的答案意味着我需要安装gfortran，但即使按照这里的说明操作：https://masuday.github.io/fortran_tutorial/install_gfortran_windows.html和安装gfortran，这也不起作用。

我该怎么办？gfortran可能偏离了目录路径吗？在msys2中键入gfortran会得到一个致命错误，即没有输入文件，即使pacman -Su gcc-fortran正确安装了

Answer 1

正确的答案是我需要将R更新到4.2，因为我忽略了更新太久。谢谢Szabolcs。