# HG changeset patch
# User Jonas Hultén <jonas@kollektivet.nu>
# Date 1634793096 -7200
#      Thu Oct 21 07:11:36 2021 +0200
# Branch develop
# Node ID 2ce5e872d50b8845961962ad2001c1910edb038d
# Parent  22b66d5eecb99df6c2eeca5e2bfe57201f8a062c
Fixed a crash when a symbol definition referred to itself.

diff --git a/jasm/assemble/assembler_impl/symbols_impl.cpp b/jasm/assemble/assembler_impl/symbols_impl.cpp
--- a/jasm/assemble/assembler_impl/symbols_impl.cpp
+++ b/jasm/assemble/assembler_impl/symbols_impl.cpp
@@ -663,11 +663,25 @@
 	// 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
 
diff --git a/jasm/exceptions/error_codes.h b/jasm/exceptions/error_codes.h
--- a/jasm/exceptions/error_codes.h
+++ b/jasm/exceptions/error_codes.h
@@ -207,6 +207,7 @@
 	AddressingModeRequiresBitSizeArgument,
 	MacroValueExpected,
 	ExpectedBooleanResult,
+	SymbolRecursion,
 
 	// assembler warnings
 	SubroutineFallthrough = 3500,
diff --git a/jasm/unit_tests/results/test_self_assignment_constant.stdout b/jasm/unit_tests/results/test_self_assignment_constant.stdout
new file mode 100644
--- /dev/null
+++ b/jasm/unit_tests/results/test_self_assignment_constant.stdout
@@ -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.
diff --git a/jasm/unit_tests/results/test_self_assignment_variable.stdout b/jasm/unit_tests/results/test_self_assignment_variable.stdout
new file mode 100644
--- /dev/null
+++ b/jasm/unit_tests/results/test_self_assignment_variable.stdout
@@ -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.
diff --git a/jasm/unit_tests/test_self_assignment_constant.asm b/jasm/unit_tests/test_self_assignment_constant.asm
new file mode 100644
--- /dev/null
+++ b/jasm/unit_tests/test_self_assignment_constant.asm
@@ -0,0 +1,7 @@
+// assembler command line arguments: 65c02 [-v0]
+
+const q = q
+
+section code, "main", 0, 100
+{
+}
diff --git a/jasm/unit_tests/test_self_assignment_variable.asm b/jasm/unit_tests/test_self_assignment_variable.asm
new file mode 100644
--- /dev/null
+++ b/jasm/unit_tests/test_self_assignment_variable.asm
@@ -0,0 +1,7 @@
+// assembler command line arguments: 65c02 [-v0]
+
+var q = q
+
+section code, "main", 0, 100
+{
+}