diff --git a/src/common/objects/dobjtype.cpp b/src/common/objects/dobjtype.cpp
index 549a9b101..b39c930f8 100644
--- a/src/common/objects/dobjtype.cpp
+++ b/src/common/objects/dobjtype.cpp
@@ -591,13 +591,13 @@ PClass *PClass::CreateDerivedClass(FName name, unsigned int size, bool *newlycre
 //
 //==========================================================================
 
-PField *PClass::AddField(FName name, PType *type, uint32_t flags)
+PField *PClass::AddField(FName name, PType *type, uint32_t flags, int fileno)
 {
 	PField *field;
 	if (!(flags & VARF_Meta))
 	{
 		unsigned oldsize = Size;
-		field = VMType->Symbols.AddField(name, type, flags, Size);
+		field = VMType->Symbols.AddField(name, type, flags, Size, nullptr, fileno);
 
 		// Only initialize the defaults if they have already been created.
 		// For ZScript this is not the case, it will first define all fields before
@@ -612,7 +612,7 @@ PField *PClass::AddField(FName name, PType *type, uint32_t flags)
 	{
 		// Same as above, but a different data storage.
 		unsigned oldsize = MetaSize;
-		field = VMType->Symbols.AddField(name, type, flags, MetaSize);
+		field = VMType->Symbols.AddField(name, type, flags, MetaSize, nullptr, fileno);
 
 		if (field != nullptr && !(flags & VARF_Native) && Meta != nullptr)
 		{
diff --git a/src/common/objects/dobjtype.h b/src/common/objects/dobjtype.h
index db3e5b974..c8464a030 100644
--- a/src/common/objects/dobjtype.h
+++ b/src/common/objects/dobjtype.h
@@ -45,7 +45,7 @@ public:
 	bool ReadAllFields(FSerializer &ar, void *addr) const;
 	int FindVirtualIndex(FName name, PFunction::Variant *variant, PFunction *parentfunc, bool exactReturnType);
 	PSymbol *FindSymbol(FName symname, bool searchparents) const;
-	PField *AddField(FName name, PType *type, uint32_t flags);
+	PField *AddField(FName name, PType *type, uint32_t flags, int fileno = 0);
 	void InitializeDefaults();
 
 	static void StaticInit();
diff --git a/src/common/scripting/core/symbols.cpp b/src/common/scripting/core/symbols.cpp
index be0b11e18..d293cbbee 100644
--- a/src/common/scripting/core/symbols.cpp
+++ b/src/common/scripting/core/symbols.cpp
@@ -137,7 +137,6 @@ PField::PField()
 {
 }
 
-
 PField::PField(FName name, PType *type, uint32_t flags, size_t offset, int bitvalue)
 	: PSymbol(name), Offset(offset), Type(type), Flags(flags)
 {
@@ -331,10 +330,12 @@ PSymbol *PSymbolTable::AddSymbol (PSymbol *sym)
 //
 //==========================================================================
 
-PField *PSymbolTable::AddField(FName name, PType *type, uint32_t flags, unsigned &Size, unsigned *Align)
+PField *PSymbolTable::AddField(FName name, PType *type, uint32_t flags, unsigned &Size, unsigned *Align, int fileno)
 {
 	PField *field = Create<PField>(name, type, flags);
 
+	field->mDefFileNo = fileno;
+
 	// The new field is added to the end of this struct, alignment permitting.
 	field->Offset = (Size + (type->Align - 1)) & ~(type->Align - 1);
 
@@ -365,10 +366,12 @@ PField *PSymbolTable::AddField(FName name, PType *type, uint32_t flags, unsigned
 //
 //==========================================================================
 
-PField *PSymbolTable::AddNativeField(FName name, PType *type, size_t address, uint32_t flags, int bitvalue)
+PField *PSymbolTable::AddNativeField(FName name, PType *type, size_t address, uint32_t flags, int bitvalue, int fileno)
 {
 	PField *field = Create<PField>(name, type, flags | VARF_Native | VARF_Transient, address, bitvalue);
 
+	field->mDefFileNo = fileno;
+
 	if (AddSymbol(field) == nullptr)
 	{ // name is already in use
 		field->Destroy();
diff --git a/src/common/scripting/core/symbols.h b/src/common/scripting/core/symbols.h
index b7d685339..de5caaae9 100644
--- a/src/common/scripting/core/symbols.h
+++ b/src/common/scripting/core/symbols.h
@@ -78,6 +78,7 @@ public:
 	uint32_t Flags;
 	int BitValue;
 	FString DeprecationMessage;
+	int mDefFileNo = 0;
 protected:
 	PField();
 };
@@ -212,8 +213,8 @@ struct PSymbolTable
 	// a symbol with the same name is already in the table. This symbol is
 	// not copied and will be freed when the symbol table is destroyed.
 	PSymbol *AddSymbol (PSymbol *sym);
-	PField *AddField(FName name, PType *type, uint32_t flags, unsigned &Size, unsigned *Align = nullptr);
-	PField *AddNativeField(FName name, PType *type, size_t address, uint32_t flags, int bitvalue);
+	PField *AddField(FName name, PType *type, uint32_t flags, unsigned &Size, unsigned *Align = nullptr, int fileno = 0);
+	PField *AddNativeField(FName name, PType *type, size_t address, uint32_t flags, int bitvalue, int fileno = 0);
 	bool ReadFields(FSerializer &ar, void *addr, const char *TypeName) const;
 	void WriteFields(FSerializer &ar, const void *addr, const void *def = nullptr) const;
 
diff --git a/src/common/scripting/core/types.cpp b/src/common/scripting/core/types.cpp
index 41671a98f..6c40aa5f0 100644
--- a/src/common/scripting/core/types.cpp
+++ b/src/common/scripting/core/types.cpp
@@ -3156,7 +3156,7 @@ PField *PStruct::AddField(FName name, PType *type, uint32_t flags)
 
 PField *PStruct::AddNativeField(FName name, PType *type, size_t address, uint32_t flags, int bitvalue)
 {
-	return Symbols.AddNativeField(name, type, address, flags, bitvalue);
+	return Symbols.AddNativeField(name, type, address, flags, bitvalue, mDefFileNo);
 }
 
 //==========================================================================
@@ -3297,7 +3297,7 @@ PClassType::PClassType(PClass *cls, int fileno)
 
 PField *PClassType::AddField(FName name, PType *type, uint32_t flags)
 {
-	return Descriptor->AddField(name, type, flags);
+	return Descriptor->AddField(name, type, flags, mDefFileNo);
 }
 
 //==========================================================================
@@ -3308,7 +3308,7 @@ PField *PClassType::AddField(FName name, PType *type, uint32_t flags)
 
 PField *PClassType::AddNativeField(FName name, PType *type, size_t address, uint32_t flags, int bitvalue)
 {
-	auto field = Symbols.AddNativeField(name, type, address, flags, bitvalue);
+	auto field = Symbols.AddNativeField(name, type, address, flags, bitvalue, mDefFileNo);
 	if (field != nullptr) Descriptor->Fields.Push(field);
 	return field;
 }