g++ is now necessary to install C++ extensions

Author: eregon

README.md

@@ -102,7 +102,7 @@ environment, for example, by unmounting system filesystems such as `/dev/shm`.
 
 ## Dependencies
 
-* [make and gcc](doc/user/installing-llvm.md) for building C and C++ extensions
+* [make, gcc and g++](doc/user/installing-llvm.md) for building C and C++ extensions
 * [libssl](doc/user/installing-libssl.md) for the `openssl` C extension
 * [libyaml](doc/user/installing-libyaml.md) for the `psych` C extension
 * [zlib](doc/user/installing-zlib.md) for the `zlib` C extension

doc/user/installing-llvm.md

@@ -12,15 +12,19 @@ The packages below are required to build C and C++ extensions.
 ### Fedora-based: RHEL, Oracle Linux, etc
 
 ```bash
-sudo dnf install make gcc
+sudo dnf install make gcc gcc-c++
 ```
 
+`gcc-c++` is only necessary for building C++ extensions.
+
 ### Debian-based: Ubuntu, etc
 
 ```bash
-sudo apt-get install make gcc
+sudo apt-get install make gcc g++
 ```
 
+`g++` is only necessary for building C++ extensions.
+
 ### macOS
 
 On macOS, make sure you have installed the command line developer tools from Xcode:

tool/docker-configs.yaml

@@ -5,6 +5,7 @@ rpm: &rpm
   openssl: openssl-devel
   yaml: libyaml-devel
   cext: gcc make
+  c++: gcc-c++
   set-locale:
     - ENV LANG=en_US.UTF-8
 
@@ -16,6 +17,7 @@ deb: &deb
   openssl: libssl-dev
   yaml: libyaml-dev
   cext: gcc make
+  c++: g++
   set-locale:
     # Uncomment the en_US.UTF-8 line in /etc/locale.gen
     - RUN sed -i '/en_US.UTF-8/s/^# //g' /etc/locale.gen

tool/docker.rb

@@ -125,6 +125,7 @@ def docker(*args)
       packages << distro.fetch('openssl')
       packages << distro.fetch('yaml')
       packages << distro.fetch('cext')
+      packages << distro.fetch('c++') if full_test
 
       proxy_vars = []
       # There is an issue with dnf + proxy in Fedora 34, install packages outside proxy to workaround