Install Ruby 3.1.7 on Apple Silicon (macOS Tahoe): missing socket extension

[tagliala]

Hello,

I'm struggling to make this specific version of Ruby install with mise, both with x64 and arm versions

OS: macOS Tahoe 26.4
mise: 2026.5.2 macos-arm64 (2026-05-07)

The main issue is that socket extension is not being compiled:

INFO  ruby@3.1.7      [1/3] *** Following extensions are not compiled:
INFO  ruby@3.1.7      [1/3] socket:
INFO  ruby@3.1.7      [1/3] 	Could not be configured. It will not be installed.
INFO  ruby@3.1.7      [1/3] 	/private/var/folders/df/2r5q9fls1dx7tt_mrq43lcb40000gn/T/ruby-build.20260508104959.47148.GKM8hH/ruby-3.1.7/ext/socket/extconf.rb:663: No such file or directory @ rb_sysopen - /usr/include/netinet6/in6.h
INFO  ruby@3.1.7      [1/3] 	Check ext/socket/mkmf.log for more details.
INFO  ruby@3.1.7      [1/3] *** Fix the problems, then remove these directories and try again if you want.

This is probably caused by the fact that /usr/include/netinet6/in6.h is not in that folder anymore (which is read only) but it is available in the MacOSX.sdk of the command line tools:

$ ls /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/netinet6/in6.h
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/netinet6/in6.h

I've tried a lot of things and all the possible AI tools to help me fix it, including setting SDKROOT manually and switch to x64, but I still haven't found a solution.

Did someone succeed to compile and use that specific version?

[tagliala]

I did try harder with GPT-5.4 Xhigh and it eventually found a solution

mise.toml

[tools]
ruby = "3.1.7"

[settings.ruby]
apply_patches = "./patches/ruby-3.1.7-darwin-socket.patch"

ruby-3.1.7-darwin-socket.patch

--- a/ext/socket/extconf.rb
+++ b/ext/socket/extconf.rb
@@ -618,65 +618,73 @@
     "udpsocket.#{$OBJEXT}",
     "unixsocket.#{$OBJEXT}",
     "unixserver.#{$OBJEXT}",
     "option.#{$OBJEXT}",
     "ancdata.#{$OBJEXT}",
     "raddrinfo.#{$OBJEXT}",
     "ifaddr.#{$OBJEXT}"
   ]
 
   if getaddr_info_ok == :wide
     if !have_type("struct in6_addr", headers) and have_type("struct in_addr6", headers)
       $defs.pop(2)
       $defs << "-Din_addr6=in6_addr"
     end
     if have_struct_member("struct in6_addr", "s6_addr8", headers)
       $defs[-1] = "-Ds6_addr=s6_addr8"
     end
     if ipv6 == "kame" && have_struct_member("struct in6_addr", "s6_addr32", headers)
       $defs[-1] = "-DFAITH"
     end
     $CPPFLAGS="-I. "+$CPPFLAGS
     $objs += ["getaddrinfo.#{$OBJEXT}"]
     $objs += ["getnameinfo.#{$OBJEXT}"]
     $defs << "-DGETADDRINFO_EMU"
   end
 
   # workaround for recent Windows SDK
   $defs << "-DIPPROTO_IPV6=IPPROTO_IPV6" if $defs.include?("-DHAVE_CONST_IPPROTO_IPV6") && !have_macro("IPPROTO_IPV6")
 
   $distcleanfiles << "constants.h" << "constdefs.*"
 
   if enable_config("socks", ENV["SOCKS_SERVER"])
     if have_library("socks5", "SOCKSinit")
       $defs << "-DSOCKS5" << "-DSOCKS"
     elsif have_library("socksd", "Rconnect") || have_library("socks", "Rconnect")
       $defs << "-DSOCKS"
     end
   end
 
   hdr = "netinet6/in6.h"
-  if /darwin/ =~ RUBY_PLATFORM and !try_compile(<<"SRC", nil, :werror=>true)
+  /darwin/ =~ RUBY_PLATFORM and
+  checking_for("if apple's #{hdr} needs s6_addr patch") {!try_compile(<<"SRC", nil, :werror=>true)} and
 #include <netinet/in.h>
 int t(struct in6_addr *addr) {return IN6_IS_ADDR_UNSPECIFIED(addr);}
 SRC
-    print "fixing apple's netinet6/in6.h ..."; $stdout.flush
-    in6 = File.read("/usr/include/#{hdr}")
+  checking_for("fixing apple's #{hdr}", "%s") do
+    file = xpopen(%w"clang -include netinet/in.h -E -xc -", in: IO::NULL) do |f|
+      re = %r[^# *\d+ *"(.*/netinet/in\.h)"]
+      Logging.message "  grep(#{re})\n"
+      f.read[re, 1]
+    end
+    Logging.message "Substitute from #{file}\n"
+
+    in6 = File.read(file)
     if in6.gsub!(/\*\(const\s+__uint32_t\s+\*\)\(const\s+void\s+\*\)\(&(\(\w+\))->s6_addr\[(\d+)\]\)/) do
         i, r = $2.to_i.divmod(4)
         if r.zero?
           "#$1->__u6_addr.__u6_addr32[#{i}]"
         else
           $&
         end
       end
       FileUtils.mkdir_p(File.dirname(hdr))
-      open(hdr, "w") {|f| f.write(in6)}
+      File.write(hdr, in6)
       $distcleanfiles << hdr
       $distcleandirs << File.dirname(hdr)
-      puts "done"
+      "done"
     else
-      puts "not needed"
+      "not needed"
     end
   end
   create_makefile("socket")
 end

[felixefelip]

@tagliala I think it's a bug from Ruby and it was only fixed from 3.2 on this commit: ruby/ruby@cb18dee

[Unknown-Guy]

This now prints mise WARN ruby.apply_patches in non-global config /Users/me/projects/mise.toml is ignored for security reasons