https://git.ruby-lang.org/ruby.git/commit/?id=ec03d13742

From ec03d137428f83f7d8819e13cb788fbd7d4e75c7 Mon Sep 17 00:00:00 2001
From: Nobuyoshi Nakada <nobu@r...>
Date: Sun, 5 Apr 2020 11:49:11 +0900
Subject: Fallback if Pathname#relative_path_from fails

It can fail due to different prefixes, e.g., drive letters or UNC
paths on DOSish platform.

diff --git a/tool/ruby_vm/helpers/dumper.rb b/tool/ruby_vm/helpers/dumper.rb
index 00c301c..98104f4 100644
--- a/tool/ruby_vm/helpers/dumper.rb
+++ b/tool/ruby_vm/helpers/dumper.rb
@@ -25,7 +25,8 @@ class RubyVM::Dumper https://github.com/ruby/ruby/blob/trunk/tool/ruby_vm/helpers/dumper.rb#L25
   end
 
   def new_erb spec
-    path  = Pathname.new(__FILE__).relative_path_from(Pathname.pwd).dirname
+    path  = Pathname.new(__FILE__)
+    path  = (path.relative_path_from(Pathname.pwd) rescue path).dirname
     path += '../views'
     path += spec
     src   = path.read mode: 'rt:utf-8:utf-8'
diff --git a/tool/ruby_vm/helpers/scanner.rb b/tool/ruby_vm/helpers/scanner.rb
index 593271a..ef6de81 100644
--- a/tool/ruby_vm/helpers/scanner.rb
+++ b/tool/ruby_vm/helpers/scanner.rb
@@ -20,7 +20,8 @@ class RubyVM::Scanner https://github.com/ruby/ruby/blob/trunk/tool/ruby_vm/helpers/scanner.rb#L20
   attr_reader :__LINE__
 
   def initialize path
-    src       = Pathname.new(__FILE__).relative_path_from(Pathname.pwd).dirname
+    src       = Pathname.new(__FILE__)
+    src       = (src.relative_path_from(Pathname.pwd) rescue src).dirname
     src      += path
     @__LINE__ = 1
     @__FILE__ = src.to_path
-- 
cgit v0.10.2


--
ML: ruby-changes@q...
Info: http://www.atdot.net/~ko1/quickml/