BUILD_UNIX.md: add g++ as a build requirement for cpu_features
@@ -36,7 +36,7 @@ sudo yum -y install cmake ncurses-devel openssl-devel readline-devel zlib-devel
## Install Requirements on Debian/Ubuntu
```bash
-sudo apt -y install cmake gcc libncurses5-dev libreadline-dev libssl-dev make zlib1g-dev
+sudo apt -y install cmake gcc g++ libncurses5-dev libreadline-dev libssl-dev make zlib1g-dev
```
