5 files changed, 32 insertions, 19 deletions
diff --git a/lib/ffi/library.rb b/lib/ffi/library.rb
index e681b3e..8af457d 100644
--- a/lib/ffi/library.rb
+++ b/lib/ffi/library.rb
@@ -295,9 +295,10 @@ module FFI
         # If it is a global struct, just attach directly to the pointer
         s = s = type.new(address) # Assigning twice to suppress unused variable warning
         self.module_eval <<-code, __FILE__, __LINE__
-          @ffi_gsvar_#{mname} = s
+          @ffi_gsvars = {} unless defined?(@ffi_gsvars)
+          @ffi_gsvars[#{mname.inspect}] = s
           def self.#{mname}
-            @ffi_gsvar_#{mname}
+            @ffi_gsvars[#{mname.inspect}]
           end
         code
 
@@ -309,12 +310,13 @@ module FFI
         # Attach to this module as mname/mname=
         #
         self.module_eval <<-code, __FILE__, __LINE__
-          @ffi_gvar_#{mname} = s
+          @ffi_gvars = {} unless defined?(@ffi_gvars)
+          @ffi_gvars[#{mname.inspect}] = s
           def self.#{mname}
-            @ffi_gvar_#{mname}[:gvar]
+            @ffi_gvars[#{mname.inspect}][:gvar]
           end
           def self.#{mname}=(value)
-            @ffi_gvar_#{mname}[:gvar] = value
+            @ffi_gvars[#{mname.inspect}][:gvar] = value
           end
         code
 
@@ -541,20 +543,30 @@ module FFI
     end
 
     def attached_functions
-      instance_variables.grep(/\A@ffi_function_(.*)/) do |m|
-        [$1, instance_variable_get(m)]
-      end.to_h
+      @ffi_functions || {}
     end
 
     def attached_variables
       (
-        instance_variables.grep(/\A@ffi_gsvar_(.*)/) do |m|
-          [$1, instance_variable_get(m).class]
+        (@ffi_gsvars || {}).map do |name, gvar|
+          [name, gvar.class]
         end +
-        instance_variables.grep(/\A@ffi_gvar_(.*)/) do |m|
-          [$1, instance_variable_get(m).layout[:gvar].type]
+        (@ffi_gvars || {}).map do |name, gvar|
+          [name, gvar.layout[:gvar].type]
         end
       ).to_h
     end
+
+    # Freeze all definitions of the module
+    #
+    # This freezes the module's definitions, so that it can be used in a Ractor.
+    # No further methods or variables can be attached and no further enums or typedefs can be created in this module afterwards.
+    def freeze
+      instance_variables.each do |name|
+        var = instance_variable_get(name)
+        FFI.make_shareable(var)
+      end
+      nil
+    end
   end
 end
diff --git a/lib/ffi/struct.rb b/lib/ffi/struct.rb
index 1283d63..725b9cb 100644
--- a/lib/ffi/struct.rb
+++ b/lib/ffi/struct.rb
@@ -219,7 +219,7 @@ module FFI
         end
         builder.size = @size if defined?(@size) && @size > builder.size
         cspec = builder.build
-        @layout = FFI.make_shareable(cspec) unless self == Struct
+        @layout = cspec unless self == Struct
         @size = cspec.size
         return cspec
       end
diff --git a/lib/ffi/struct_layout.rb b/lib/ffi/struct_layout.rb
index d5a78a7..3fd68cb 100644
--- a/lib/ffi/struct_layout.rb
+++ b/lib/ffi/struct_layout.rb
@@ -80,8 +80,8 @@ module FFI
 
     class Mapped < Field
       def initialize(name, offset, type, orig_field)
-        super(name, offset, type)
         @orig_field = orig_field
+        super(name, offset, type)
       end
 
       def get(ptr)
diff --git a/lib/ffi/struct_layout_builder.rb b/lib/ffi/struct_layout_builder.rb
index 5488033..d7d26a2 100644
--- a/lib/ffi/struct_layout_builder.rb
+++ b/lib/ffi/struct_layout_builder.rb
@@ -97,7 +97,7 @@ module FFI
 
 
     # List of number types
-    NUMBER_TYPES = FFI.make_shareable([
+    NUMBER_TYPES = [
       Type::INT8,
       Type::UINT8,
       Type::INT16,
@@ -112,7 +112,7 @@ module FFI
       Type::FLOAT64,
       Type::LONGDOUBLE,
       Type::BOOL,
-    ])
+    ].freeze
 
     # @param [String, Symbol] name name of the field
     # @param [Array, DataConverter, Struct, StructLayout::Field, Symbol, Type] type type of the field
diff --git a/lib/ffi/variadic.rb b/lib/ffi/variadic.rb
index 800d121..246b52f 100644
--- a/lib/ffi/variadic.rb
+++ b/lib/ffi/variadic.rb
@@ -54,11 +54,12 @@ module FFI
       invoker = self
       params = "*args"
       call = "call"
-      mod.module_eval <<-code
-        @ffi_function_#{mname} = invoker
+      mod.module_eval <<-code, __FILE__, __LINE__
+        @ffi_functions = {} unless defined?(@ffi_functions)
+        @ffi_functions[#{mname.inspect}] = invoker
 
         def self.#{mname}(#{params})
-          @ffi_function_#{mname}.#{call}(#{params})
+          @ffi_functions[#{mname.inspect}].#{call}(#{params})
         end
 
         define_method(#{mname.inspect}, &method(:#{mname}))