From: Mikko Rasa <tdb@tdb.fi>
Date: Fri, 6 Jan 2017 13:18:42 +0000 (+0200)
Subject: Properly handle the legacy replacement of fragment shader output
X-Git-Url: http://git.tdb.fi/?p=libs%2Fgl.git;a=commitdiff_plain;h=f02b9bf0834d2a9422cfd812159352b428b46bb6

Properly handle the legacy replacement of fragment shader output

Assignment targets to the output variable need to be cleared, lest the
unused variable locator tries to access deleted nodes.
---

diff --git a/source/programcompiler.cpp b/source/programcompiler.cpp
index f9a14f2f..fd27839d 100644
--- a/source/programcompiler.cpp
+++ b/source/programcompiler.cpp
@@ -1494,11 +1494,13 @@ void ProgramCompiler::NodeRemover::visit(VariableDeclaration &var)
 
 
 ProgramCompiler::LegacyConverter::LegacyConverter():
-	target_version(get_glsl_version())
+	target_version(get_glsl_version()),
+	frag_out(0)
 { }
 
 ProgramCompiler::LegacyConverter::LegacyConverter(const Version &v):
-	target_version(v)
+	target_version(v),
+	frag_out(0)
 { }
 
 bool ProgramCompiler::LegacyConverter::check_version(const Version &feature_version)
@@ -1513,7 +1515,7 @@ bool ProgramCompiler::LegacyConverter::check_version(const Version &feature_vers
 
 void ProgramCompiler::LegacyConverter::visit(VariableReference &var)
 {
-	if(var.name==frag_out_name && !check_version(Version(1, 30)))
+	if(var.declaration==frag_out && !check_version(Version(1, 30)))
 	{
 		var.name = "gl_FragColor";
 		var.declaration = 0;
@@ -1525,6 +1527,13 @@ void ProgramCompiler::LegacyConverter::visit(VariableReference &var)
 		type = string();
 }
 
+void ProgramCompiler::LegacyConverter::visit(Assignment &assign)
+{
+	TraversingVisitor::visit(assign);
+	if(assign.target_declaration==frag_out && !check_version(Version(1, 30)))
+		assign.target_declaration = 0;
+}
+
 void ProgramCompiler::LegacyConverter::visit(FunctionCall &call)
 {
 	if(call.name=="texture" && !call.declaration && !check_version(Version(1, 30)))
@@ -1581,7 +1590,7 @@ void ProgramCompiler::LegacyConverter::visit(VariableDeclaration &var)
 	{
 		if(stage->type==FRAGMENT && var.interface=="out")
 		{
-			frag_out_name = var.name;
+			frag_out = &var;
 			remove_node = true;
 		}
 	}
diff --git a/source/programcompiler.h b/source/programcompiler.h
index 5bb71474..e159078a 100644
--- a/source/programcompiler.h
+++ b/source/programcompiler.h
@@ -330,7 +330,7 @@ private:
 	{
 		Version target_version;
 		std::string type;
-		std::string frag_out_name;
+		ProgramSyntax::VariableDeclaration *frag_out;
 
 		LegacyConverter();
 		LegacyConverter(const Version &);
@@ -338,6 +338,7 @@ private:
 		bool check_version(const Version &);
 		using Visitor::visit;
 		virtual void visit(ProgramSyntax::VariableReference &);
+		virtual void visit(ProgramSyntax::Assignment &);
 		virtual void visit(ProgramSyntax::FunctionCall &);
 		virtual void visit(ProgramSyntax::VariableDeclaration &);
 		virtual void visit(ProgramSyntax::InterfaceBlock &);