R更新后无法安装包：新位置重装及编译问题求助

问题背景 #

我是R新手，有少量使用经验。更新R和RStudio后所有包无法安装，以安装dplyr为例出现编译失败错误：

> install.packages("dplyr")

  There is a binary version available but the source version is later:
      binary source needs_compilation
dplyr 1.0.10  1.1.0              TRUE

Do you want to install from sources the package which needs compilation? (Yes/no/cancel) Yes
installing the source package ‘dplyr’

trying URL 'https://cran.rstudio.com/src/contrib/dplyr_1.1.0.tar.gz'
Content type 'application/x-gzip' length 1068347 bytes (1.0 MB)
==================================================
downloaded 1.0 MB

* installing *source* package ‘dplyr’ ...
** package ‘dplyr’ successfully unpacked and MD5 sums checked
** using staged installation
** libs
/usr/local/Cellar/gcc/9.2.0/bin/g++-7 -I"/Library/Frameworks/R.framework/Resources/include" -DNDEBUG   -I/usr/local/include   -fPIC  -Wall -g -O2  -c chop.cpp -o chop.o
/bin/sh: /usr/local/Cellar/gcc/9.2.0/bin/g++-7: No such file or directory
make: *** [chop.o] Error 127
ERROR: compilation failed for package ‘dplyr’
* removing ‘/Library/Frameworks/R.framework/Versions/4.2/Resources/library/dplyr’
* restoring previous ‘/Library/Frameworks/R.framework/Versions/4.2/Resources/library/dplyr’
Warning in install.packages :
  installation of package ‘dplyr’ had non-zero exit status

The downloaded source packages are in
    ‘/private/var/folders/k7/pbrcjpr517x06fhvnkvbq0nc0000gp/T/RtmpAODLeZ/downloaded_packages’
> 

排查结果 #

经检查，R试图调用旧版本g++-7，但终端显示当前gcc版本为12.2.0，对应g++-12：

(base) Liams-MacBook-Pro:~ lessig7$ brew list gcc
/usr/local/Cellar/gcc/12.2.0/bin/c++-12
/usr/local/Cellar/gcc/12.2.0/bin/cpp-12
/usr/local/Cellar/gcc/12.2.0/bin/g++-12
/usr/local/Cellar/gcc/12.2.0/bin/gcc-12
/usr/local/Cellar/gcc/12.2.0/bin/gcc-ar-12
/usr/local/Cellar/gcc/12.2.0/bin/gcc-nm-12
/usr/local/Cellar/gcc/12.2.0/bin/gcc-ranlib-12
/usr/local/Cellar/gcc/12.2.0/bin/gcov-12
/usr/local/Cellar/gcc/12.2.0/bin/gcov-dump-12
/usr/local/Cellar/gcc/12.2.0/bin/gcov-tool-12
/usr/local/Cellar/gcc/12.2.0/bin/gfortran
/usr/local/Cellar/gcc/12.2.0/bin/gfortran-12
/usr/local/Cellar/gcc/12.2.0/bin/lto-dump-12
/usr/local/Cellar/gcc/12.2.0/bin/x86_64-apple-darwin21-c++-12
/usr/local/Cellar/gcc/12.2.0/bin/x86_64-apple-darwin21-g++-12
/usr/local/Cellar/gcc/12.2.0/bin/x86_64-apple-darwin21-gcc-12
/usr/local/Cellar/gcc/12.2.0/bin/x86_64-apple-darwin21-gcc-ar-12
/usr/local/Cellar/gcc/12.2.0/bin/x86_64-apple-darwin21-gcc-nm-12
/usr/local/Cellar/gcc/12.2.0/bin/x86_64-apple-darwin21-gcc-ranlib-12
/usr/local/Cellar/gcc/12.2.0/bin/x86_64-apple-darwin21-gfortran-12
/usr/local/Cellar/gcc/12.2.0/include/c++/ (806 files)
/usr/local/Cellar/gcc/12.2.0/lib/gcc/ (719 files)

错误尝试 #

我曾错误指定编译器路径作为包安装目录，导致权限错误：

install.packages("dplyr", lib="/usr/local/Cellar/gcc/12.2.0/bin/c++-12/Library/Frameworks/R.framework/Resources/include")

出现报错：

install.packages("dplyr", lib="/usr/local/Cellar/gcc/12.2.0/bin/c++-12/Library/Frameworks/R.framework/Resources/include")
Warning in install.packages :
  'lib = "/usr/local/Cellar/gcc/12.2.0/bin/c++-12/Library/Frameworks/R.framework/Resources/include"' is not writable
Would you like to use a personal library instead? (yes/No/cancel) 
Error in install.packages : unable to install packages
> 

install.packages("dplyr", lib="/usr/local/Cellar/gcc/12.2.0/bin/c++-12/Library/Frameworks/R.framework/Resources/include")

解决方案 #

1. 让R识别当前g++版本 #

• 方法一：创建软链接映射旧编译器路径
  在终端执行以下命令，让R寻找的g++-7指向当前的g++-12：

  # 先创建旧版本gcc的bin目录（如果不存在）
  sudo mkdir -p /usr/local/Cellar/gcc/9.2.0/bin
  # 创建软链接
  sudo ln -s /usr/local/Cellar/gcc/12.2.0/bin/g++-12 /usr/local/Cellar/gcc/9.2.0/bin/g++-7
  

• 方法二：修改R环境变量指定编译器
  在R控制台执行以下命令，临时指定编译器路径：

  Sys.setenv(CXX = "/usr/local/Cellar/gcc/12.2.0/bin/g++-12")
  Sys.setenv(CC = "/usr/local/Cellar/gcc/12.2.0/bin/gcc-12")
  

  若要永久生效，将上述两行代码添加到用户主目录下的.Rprofile文件中（没有则新建），每次启动R时会自动加载。

2. 正确安装R包 #

• 使用默认路径安装：不要手动指定lib参数到编译器路径，直接执行默认安装命令：

  install.packages("dplyr")
  

  若提示权限不足，选择"yes"使用个人库（推荐），避免使用sudo修改系统目录权限。

• 优先安装二进制版本：如果不想编译源码，直接指定安装二进制包，跳过源码编译步骤：

  install.packages("dplyr", type = "binary")
  

内容的提问来源于stack exchange，提问作者lwe