From d80750e7c20ea061f210b756196cc844b762b852 Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Fri, 5 Mar 2021 13:22:47 +0200
Subject: [PATCH] Resolve the return types of functions

---
 source/glsl/generate.cpp | 7 +++++++
 source/glsl/generate.h   | 1 +
 source/glsl/syntax.cpp   | 6 ++++--
 source/glsl/syntax.h     | 1 +
 source/glsl/validate.cpp | 7 +++++++
 source/glsl/validate.h   | 1 +
 6 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/source/glsl/generate.cpp b/source/glsl/generate.cpp
index 8626cac6..433d506e 100644
--- a/source/glsl/generate.cpp
+++ b/source/glsl/generate.cpp
@@ -162,6 +162,13 @@ void TypeResolver::visit(VariableDeclaration &var)
 		var.type_declaration = i->second;
 }
 
+void TypeResolver::visit(FunctionDeclaration &func)
+{
+	map<string, TypeDeclaration *>::iterator i = stage->types.find(func.return_type);
+	func.return_type_declaration = (i!=stage->types.end() ? i->second : 0);
+	TraversingVisitor::visit(func);
+}
+
 
 VariableResolver::VariableResolver():
 	stage(0),
diff --git a/source/glsl/generate.h b/source/glsl/generate.h
index d303af36..d4e570ab 100644
--- a/source/glsl/generate.h
+++ b/source/glsl/generate.h
@@ -71,6 +71,7 @@ private:
 	virtual void visit(ImageTypeDeclaration &);
 	virtual void visit(StructDeclaration &);
 	virtual void visit(VariableDeclaration &);
+	virtual void visit(FunctionDeclaration &);
 };
 
 /** Resolves variable references.  Variable references which match the name
diff --git a/source/glsl/syntax.cpp b/source/glsl/syntax.cpp
index e20d6c26..c8058c4f 100644
--- a/source/glsl/syntax.cpp
+++ b/source/glsl/syntax.cpp
@@ -347,7 +347,8 @@ void InterfaceBlock::visit(NodeVisitor &visitor)
 
 
 FunctionDeclaration::FunctionDeclaration():
-	definition(0)
+	definition(0),
+	return_type_declaration(0)
 { }
 
 FunctionDeclaration::FunctionDeclaration(const FunctionDeclaration &other):
@@ -356,7 +357,8 @@ FunctionDeclaration::FunctionDeclaration(const FunctionDeclaration &other):
 	name(other.name),
 	parameters(other.parameters),
 	body(other.body),
-	definition(other.definition==&other ? this : 0)
+	definition(other.definition==&other ? this : 0),
+	return_type_declaration(0)
 { }
 
 void FunctionDeclaration::visit(NodeVisitor &visitor)
diff --git a/source/glsl/syntax.h b/source/glsl/syntax.h
index 62c289d9..0379a911 100644
--- a/source/glsl/syntax.h
+++ b/source/glsl/syntax.h
@@ -404,6 +404,7 @@ struct FunctionDeclaration: Statement
 	Block body;
 
 	FunctionDeclaration *definition;
+	TypeDeclaration *return_type_declaration;
 
 	FunctionDeclaration();
 	FunctionDeclaration(const FunctionDeclaration &);
diff --git a/source/glsl/validate.cpp b/source/glsl/validate.cpp
index 8e5e996c..e6f0c653 100644
--- a/source/glsl/validate.cpp
+++ b/source/glsl/validate.cpp
@@ -201,6 +201,13 @@ void ReferenceValidator::visit(VariableDeclaration &var)
 	TraversingVisitor::visit(var);
 }
 
+void ReferenceValidator::visit(FunctionDeclaration &func)
+{
+	if(!func.return_type_declaration)
+		error(func, format("Use of undeclared type '%s'", func.return_type));
+	TraversingVisitor::visit(func);
+}
+
 } // namespace SL
 } // namespace GL
 } // namespace Msp
diff --git a/source/glsl/validate.h b/source/glsl/validate.h
index e4b9edae..3efa5141 100644
--- a/source/glsl/validate.h
+++ b/source/glsl/validate.h
@@ -78,6 +78,7 @@ private:
 	virtual void visit(VariableReference &);
 	virtual void visit(InterfaceBlockReference &);
 	virtual void visit(VariableDeclaration &);
+	virtual void visit(FunctionDeclaration &);
 };
 
 } // namespace SL
-- 
2.43.0