diff --git a/spec/compiler/codegen/const_spec.cr b/spec/compiler/codegen/const_spec.cr
index 0c8342261bd0c62dd593213991de357302d3e96f..7aab57a8315af99004c263fc2e0c0b34bb1e8ec4 100644
--- a/spec/compiler/codegen/const_spec.cr
+++ b/spec/compiler/codegen/const_spec.cr
@@ -87,7 +87,11 @@ describe "Codegen: const" do
end
it "declare constants in right order" do
- run("A = 1 + 1; B = true ? A : 0; B").to_i.should eq(2)
+ run(%(
+ A = 1 + 1
+ B = true ? A : 0
+ B
+ )).to_i.should eq(2)
end
it "uses correct types lookup" do
@@ -255,4 +259,39 @@ describe "Codegen: const" do
Foo::Y.value
)).to_i.should eq(1)
end
+
+ it "codegens constant that refers to another one later in the file through a method call" do
+ build(%(
+ def foo
+ 1
+ end
+
+ class Some
+ CONST_1 = Some.method
+ CONST_2 = foo
+
+ def self.method
+ CONST_2
+ end
+ end
+
+ Some::CONST_1
+ ))
+ end
+
+ it "codegens constant that refers to another one later, twice" do
+ build(%(
+ def foo
+ 1
+ end
+
+ class Some
+ CONST_1 = CONST_2
+ CONST_2 = CONST_3
+ CONST_3 = foo
+ end
+
+ Some::CONST_1
+ ))
+ end
end
diff --git a/spec/compiler/type_inference/const_spec.cr b/spec/compiler/type_inference/const_spec.cr
index ad04e2c11523945058bd7d431dc0a3849251aba1..46484dcd92d6be434dc4f8a42517ded519b166af 100755
--- a/spec/compiler/type_inference/const_spec.cr
+++ b/spec/compiler/type_inference/const_spec.cr
@@ -162,4 +162,14 @@ describe "Type inference: const" do
B::CONSTANT
)) { bool }
end
+
+ it "detects recursive constant definition" do
+ assert_error %(
+ A = B
+ B = A
+
+ A
+ ),
+ "recursive constant definition: A -> B -> A"
+ end
end
diff --git a/spec/spec_helper.cr b/spec/spec_helper.cr
index c1b7a973bbc312fb21bc1160ba6da848d33e45d0..dca831fcf4b9e328859f1cdad507b8ab29328384 100644
--- a/spec/spec_helper.cr
+++ b/spec/spec_helper.cr
@@ -130,7 +130,7 @@ end
def build(code)
node = parse code
result = infer_type node
- result.program.build result.node, single_module: true
+ result.program.build result.node, single_module: false
end
class Crystal::SpecRunOutput
diff --git a/src/compiler/crystal/codegen/codegen.cr b/src/compiler/crystal/codegen/codegen.cr
index 1c17c9f545630b089fd3022ff4e5d38c113a676f..301e5a0834e175802585ba9018c01f1b6c6aea7a 100644
--- a/src/compiler/crystal/codegen/codegen.cr
+++ b/src/compiler/crystal/codegen/codegen.cr
@@ -640,7 +640,7 @@ module Crystal
# Initialize constants if they are used
if target.is_a?(Path)
const = target.target_const.not_nil!
- declare_const(const)
+ declare_const const
@last = llvm_nil
return false
end
@@ -874,10 +874,10 @@ module Crystal
if const = node.target_const
global_name = const.llvm_name
- # TODO: the `||` part is to take care of constants that, for their
- # initialization, depend on a constant that comes later in the code.
- # We should maybe give an error in the type inference phase in this case.
- global = @main_mod.globals[global_name]? || declare_const(const).not_nil!
+ global = @main_mod.globals[global_name]?
+ unless global
+ node.raise "Bug: global not found for #{const}"
+ end
if @llvm_mod != @main_mod
global = @llvm_mod.globals[global_name]?
@@ -902,7 +902,17 @@ module Crystal
end
def declare_const(const, global_name = const.llvm_name)
- return nil unless const.used
+ return unless const.used
+
+ # First declare constants this constant depends on
+ const.dependencies.try &.each do |dep|
+ declare_const dep
+ end
+
+ # The constant might be already codegened
+ if global = @main_mod.globals[global_name]?
+ return global
+ end
global = @main_mod.globals.add(llvm_type(const.value.type), global_name)
diff --git a/src/compiler/crystal/program.cr b/src/compiler/crystal/program.cr
index 0d951f441d58127f2377ccc145a9f63be4335011..95a89f968ca8a98f2b292ebb77ef7132ac0406a3 100644
--- a/src/compiler/crystal/program.cr
+++ b/src/compiler/crystal/program.cr
@@ -15,6 +15,7 @@ module Crystal
getter splat_expansions
property vars
property literal_expander
+ getter consts_stack
def initialize
super(self, self, "main")
@@ -109,6 +110,7 @@ module Crystal
@macro_expander = MacroExpander.new self
@def_macros = [] of Def
@splat_expansions = {} of Def => Type
+ @consts_stack = [] of Const
define_primitives
end
@@ -147,6 +149,18 @@ module Crystal
flags.add(flag)
end
+ def push_const(const)
+ if last_const = @consts_stack.last?
+ last_const.add_dependency const
+ end
+
+ @consts_stack.push const
+ end
+
+ def pop_const
+ @consts_stack.pop
+ end
+
def program
self
end
diff --git a/src/compiler/crystal/semantic/type_inference.cr b/src/compiler/crystal/semantic/type_inference.cr
index b227430f87c3e24ea11c63ed85015bf86e3ffed0..105dd27fd8c332dab081894604ea1a2e8278c28e 100644
--- a/src/compiler/crystal/semantic/type_inference.cr
+++ b/src/compiler/crystal/semantic/type_inference.cr
@@ -1772,12 +1772,22 @@ module Crystal
case type
when Const
unless type.value.type?
+ if type.visited?
+ node.raise "recursive constant definition: #{@mod.consts_stack.join " -> "} -> #{type}"
+ end
+
+ type.visited = true
+
meta_vars = MetaVars.new
const_def = Def.new("const", [] of Arg)
type_visitor = TypeVisitor.new(@mod, meta_vars, const_def)
type_visitor.types = type.scope_types
type_visitor.scope = type.scope
+
+ @mod.push_const type
type.value.accept type_visitor
+ @mod.pop_const
+
type.vars = const_def.vars
end
node.target_const = type
diff --git a/src/compiler/crystal/types.cr b/src/compiler/crystal/types.cr
index 8690cb86d7453346b5c698cad335590ab0c085df..8d2770f8712ec001810afc30e54917485e40ace2 100644
--- a/src/compiler/crystal/types.cr
+++ b/src/compiler/crystal/types.cr
@@ -2551,10 +2551,18 @@ module Crystal
getter scope
property! vars
property used
+ property dependencies
+ property? visited
def initialize(program, container, name, @value, @scope_types = [] of Type, @scope = nil)
super(program, container, name)
@used = false
+ @visited = false
+ end
+
+ def add_dependency(const)
+ dependencies = @dependencies ||= [] of Const
+ dependencies.push const
end
def type_desc