Atomically initialize constants and class variables

spec/compiler/codegen/class_spec.cr

@@ -447,6 +447,8 @@ describe "Code gen: class" do
 
   it "allows using self in class scope" do
     run(%(
+      require "prelude"
+
       class Foo
         def self.foo
           1
@@ -713,6 +715,8 @@ describe "Code gen: class" do
 
   it "codegens singleton (#718)" do
     run(%(
+      require "prelude"
+
       class Singleton
         @@instance = new
 

spec/compiler/codegen/class_var_spec.cr

@@ -106,6 +106,8 @@ describe "Codegen: class var" do
 
   it "uses var in class var initializer" do
     run(%(
+      require "prelude"
+
       class Foo
         @@var : Int32
         @@var = begin
@@ -128,6 +130,8 @@ describe "Codegen: class var" do
 
   it "reads simple class var before another complex one" do
     run(%(
+      require "prelude"
+
       class Foo
         @@var2 : Int32
         @@var2 = @@var &+ 1
@@ -145,6 +149,8 @@ describe "Codegen: class var" do
 
   it "initializes class var of union with single type" do
     run(%(
+      require "prelude"
+
       class Foo
         @@var : Int32 | String
         @@var = 42
@@ -196,6 +202,8 @@ describe "Codegen: class var" do
 
   it "initializes dependent constant before class var" do
     run(%(
+      require "prelude"
+
       def foo
         a = 1
         b = 2
@@ -233,6 +241,8 @@ describe "Codegen: class var" do
 
   it "doesn't use nilable type for initializer" do
     run(%(
+      require "prelude"
+
       class Foo
         @@foo : Int32?
         @@foo = 42
@@ -250,7 +260,9 @@ describe "Codegen: class var" do
   end
 
   it "codegens class var with begin and vars" do
-    run("
+    run(%(
+      require "prelude"
+
       class Foo
         @@foo : Int32
         @@foo = begin
@@ -265,11 +277,13 @@ describe "Codegen: class var" do
       end
 
       Foo.foo
-      ").to_i.should eq(3)
+      )).to_i.should eq(3)
   end
 
   it "codegens class var with type declaration begin and vars" do
-    run("
+    run(%(
+      require "prelude"
+
       class Foo
         @@foo : Int32 = begin
           a = 1
@@ -283,7 +297,7 @@ describe "Codegen: class var" do
       end
 
       Foo.foo
-      ").to_i.should eq(3)
+      )).to_i.should eq(3)
   end
 
   it "codegens class var with nilable reference type" do
@@ -338,6 +352,8 @@ describe "Codegen: class var" do
 
   it "gets pointerof class var complex constant" do
     run(%(
+      require "prelude"
+
       z = Foo.foo
 
       class Foo

spec/compiler/codegen/const_spec.cr

@@ -87,14 +87,18 @@ describe "Codegen: const" do
 
   it "declare constants in right order" do
     run(%(
+      require "prelude"
+
       CONST1 = 1 + 1
       CONST2 = true ? CONST1 : 0
       CONST2
       )).to_i.should eq(2)
   end
 
   it "uses correct types lookup" do
-    run("
+    run(%(
+      require "prelude"
+
       module Moo
         class B
           def foo
@@ -110,11 +114,13 @@ describe "Codegen: const" do
       end
 
       foo
-      ").to_i.should eq(1)
+      )).to_i.should eq(1)
   end
 
   it "codegens variable assignment in const" do
-    run("
+    run(%(
+      require "prelude"
+
       class Foo
         def initialize(@x : Int32)
         end
@@ -134,11 +140,13 @@ describe "Codegen: const" do
       end
 
       foo
-      ").to_i.should eq(1)
+      )).to_i.should eq(1)
   end
 
   it "declaring var" do
-    run("
+    run(%(
+      require "prelude"
+
       BAR = begin
         a = 1
         while 1 == 2
@@ -153,7 +161,7 @@ describe "Codegen: const" do
       end
 
       Foo.new.compile
-      ").to_i.should eq(1)
+      )).to_i.should eq(1)
   end
 
   it "initialize const that might raise an exception" do
@@ -171,7 +179,9 @@ describe "Codegen: const" do
   end
 
   it "allows implicit self in constant, called from another class (bug)" do
-    run("
+    run(%(
+      require "prelude"
+
       module Foo
         def self.foo
           1
@@ -187,11 +197,13 @@ describe "Codegen: const" do
       end
 
       Bar.new.bar
-      ").to_i.should eq(1)
+      )).to_i.should eq(1)
   end
 
   it "codegens two consts with same variable name" do
-    run("
+    run(%(
+      require "prelude"
+
       CONST1 = begin
             a = 1
           end
@@ -201,11 +213,13 @@ describe "Codegen: const" do
           end
 
       (CONST1 + CONST2).to_i
-      ").to_i.should eq(3)
+      )).to_i.should eq(3)
   end
 
   it "works with variable declared inside if" do
     run(%(
+      require "prelude"
+
       FOO = begin
         if 1 == 2
           x = 3
@@ -220,6 +234,8 @@ describe "Codegen: const" do
 
   it "codegens constant that refers to another constant that is a struct" do
     run(%(
+      require "prelude"
+
       struct Foo
         X = Foo.new(1)
         Y = X
@@ -281,6 +297,8 @@ describe "Codegen: const" do
 
   it "uses const before declaring it (hoisting)" do
     run(%(
+      require "prelude"
+
       x = CONST
 
       CONST = foo
@@ -342,6 +360,8 @@ describe "Codegen: const" do
 
   it "gets pointerof constant" do
     run(%(
+      require "prelude"
+
       z = pointerof(FOO).value
       FOO = 10
       z
@@ -350,6 +370,8 @@ describe "Codegen: const" do
 
   it "gets pointerof complex constant" do
     run(%(
+      require "prelude"
+
       z = pointerof(FOO).value
       FOO = begin
         a = 10
@@ -446,4 +468,42 @@ describe "Codegen: const" do
 
     mod.to_s.should_not contain("CONST")
   end
+
+  it "synchronize initialization of contants" do
+    run(%(
+      require "prelude"
+
+      def foo
+        v1, v2 = 1, 1
+        rand(100000..10000000).times do
+          v1, v2 = v2, v1 + v2
+        end
+        v2
+      end
+
+      ch = Channel(Int32).new
+
+      10.times do
+        spawn do
+          ch.send X
+        end
+      end
+
+      X = foo
+
+      def test(ch)
+        expected = X
+
+        10.times do
+          if ch.receive != expected
+            return false
+          end
+        end
+
+        true
+      end
+
+      test(ch)
+    )).to_b.should be_true
+  end
 end

spec/compiler/codegen/debug_spec.cr

@@ -107,6 +107,8 @@ describe "Code gen: debug" do
 
   it "has correct debug location after constant initialization in call with block (#4719)" do
     codegen(%(
+      require "prelude"
+
       fun __crystal_malloc_atomic(size : UInt32) : Void*
         x = uninitialized Void*
         x

spec/compiler/codegen/hooks_spec.cr

@@ -115,7 +115,9 @@ describe "Code gen: hooks" do
   end
 
   it "does inherited macro before class body" do
-    run("
+    run(%(
+      require "prelude"
+
       class Global
         @@x = 123
 
@@ -142,7 +144,7 @@ describe "Code gen: hooks" do
       end
 
       Bar.y
-      ").to_i.should eq(123)
+      )).to_i.should eq(123)
   end
 
   it "does finished" do

spec/compiler/codegen/macro_spec.cr

@@ -663,6 +663,8 @@ describe "Code gen: macro" do
 
   it "transforms hooks (bug)" do
     codegen(%(
+      require "prelude"
+
       module GC
         def self.add_finalizer(object : T)
           object.responds_to?(:finalize)
@@ -800,6 +802,8 @@ describe "Code gen: macro" do
 
   it "copies base macro def to sub-subtype even after it was copied to a subtype (#448)" do
     run(%(
+      require "prelude"
+
       class Object
         def class_name : String
           {{@type.name.stringify}}

spec/compiler/codegen/pointer_spec.cr

@@ -250,10 +250,11 @@ describe "Code gen: pointer" do
   end
 
   it "gets pointer to constant" do
-    run("
+    run(%(
+      require "prelude"
       FOO = 1
       pointerof(FOO).value
-    ").to_i.should eq(1)
+    )).to_i.should eq(1)
   end
 
   it "passes pointer of pointer to method" do
@@ -324,6 +325,8 @@ describe "Code gen: pointer" do
 
   it "does pointerof class variable with class" do
     run(%(
+      require "prelude"
+
       class Bar
         def initialize(@x : Int32)
         end

spec/compiler/codegen/proc_spec.cr

@@ -595,6 +595,8 @@ describe "Code gen: proc" do
 
   it "codegens proc to implicit self in constant (#647)" do
     run(%(
+      require "prelude"
+
       module Foo
         def self.blah
           1