@@ 663,11 663,25 @@ void Assembler::evaluate_symbol(bool gen
 	// and previous pass references must be allowed for constants.
 
 	if (variable_reference != nullptr) {
-		value.type = ValueType::ValueReference;
-		value.set_found_in_current_pass(found_in_current_pass);
-		value.variable_reference_hash = combined_hash;
-		value.type_hash = _static_value_reference_type;
+		if (variable_reference->type_hash == 0) {
+			// This can happen if the symbol is created and used in the same expression.
+			// So the variable hasn't been properly initialized yet.
+			set_unknown(value);
+			value.global = true;
+			value.storage_type = StorageType::Constant; // Not entirely sure what to set this to. Type must be checked before this.
+			
+			if (generate) {
+				std::stringstream ss;
+				ss << "A symbol's definition can't refer to itself.";
+				report_error(component.source_location, AssemblyErrorCodes::SymbolRecursion, ss.str());
+			}
 
+		} else {
+			value.type = ValueType::ValueReference;
+			value.set_found_in_current_pass(found_in_current_pass);
+			value.variable_reference_hash = combined_hash;
+			value.type_hash = _static_value_reference_type;
+		}
 	} else {
 		// symbol was not found or is ambiguous
 

          

@@ 207,6 207,7 @@ enum class AssemblyErrorCodes
 	AddressingModeRequiresBitSizeArgument,
 	MacroValueExpected,
 	ExpectedBooleanResult,
+	SymbolRecursion,
 
 	// assembler warnings
 	SubroutineFallthrough = 3500,

          

@@ 0,0 1,2 @@ 
+unit_tests/test_self_assignment_constant.asm(3,11) : Error 3116 : A symbol's definition can't refer to itself.
+Assembly ended with errors.

          

@@ 0,0 1,2 @@ 
+unit_tests/test_self_assignment_variable.asm(3,9) : Error 3116 : A symbol's definition can't refer to itself.
+Assembly ended with errors.

          

@@ 0,0 1,7 @@ 
+// assembler command line arguments: 65c02 [-v0]
+
+const q = q
+
+section code, "main", 0, 100
+{
+}

          

@@ 0,0 1,7 @@ 
+// assembler command line arguments: 65c02 [-v0]
+
+var q = q
+
+section code, "main", 0, 100
+{
+}