diff --git a/src/scripting/thingdef_data.cpp b/src/scripting/thingdef_data.cpp
index a4dfbc16c5..210fb7cfc3 100644
--- a/src/scripting/thingdef_data.cpp
+++ b/src/scripting/thingdef_data.cpp
@@ -530,8 +530,8 @@ FFlagDef *FindFlag (const PClass *type, const char *part1, const char *part2, bo
 			{
 				forInternalFlags.fieldsize = 4;
 				forInternalFlags.name = "";
-				forInternalFlags.flagbit = field->bitval >= 0? 1 << field->bitval : DEPF_UNUSED;
-				forInternalFlags.structoffset = field->bitval >= 0 ? field->Offset->Offset : -1;
+				forInternalFlags.flagbit = field->Offset? 1 << field->bitval : DEPF_UNUSED;
+				forInternalFlags.structoffset = field->Offset? (int)field->Offset->Offset : -1;
 				forInternalFlags.varflags = 0;
 				return &forInternalFlags;
 			}
@@ -548,8 +548,8 @@ FFlagDef *FindFlag (const PClass *type, const char *part1, const char *part2, bo
 			{
 				forInternalFlags.fieldsize = 4;
 				forInternalFlags.name = "";
-				forInternalFlags.flagbit = field->bitval >= 0 ? 1 << field->bitval : DEPF_UNUSED;
-				forInternalFlags.structoffset = field->bitval >= 0 ? field->Offset->Offset : -1;
+				forInternalFlags.flagbit = field->Offset ? 1 << field->bitval : DEPF_UNUSED;
+				forInternalFlags.structoffset = field->Offset ? (int)field->Offset->Offset : -1;
 				forInternalFlags.varflags = 0;
 				return &forInternalFlags;
 			}
diff --git a/src/scripting/zscript/zcc_compile.cpp b/src/scripting/zscript/zcc_compile.cpp
index 512a2f801b..52ab582faf 100644
--- a/src/scripting/zscript/zcc_compile.cpp
+++ b/src/scripting/zscript/zcc_compile.cpp
@@ -1468,15 +1468,19 @@ bool ZCCCompiler::CompileFlagDefs(PClass *type, TArray<ZCC_FlagDef *> &Propertie
 		}
 		else
 		{
-			field = dyn_cast<PField>(type->FindSymbol(referenced, true));
-			if (field == nullptr)
+			if (referenced != NAME_None)
 			{
-				Error(p, "Variable %s not found in %s", referenced.GetChars(), type->TypeName.GetChars());
-			}
-			if (!field->Type->isInt() || field->Type->Size != 4)
-			{
-				Error(p, "Variable %s in %s must have a size of 4 bytes for use as flag storage", referenced.GetChars(), type->TypeName.GetChars());
+				field = dyn_cast<PField>(type->FindSymbol(referenced, true));
+				if (field == nullptr)
+				{
+					Error(p, "Variable %s not found in %s", referenced.GetChars(), type->TypeName.GetChars());
+				}
+				if (!field->Type->isInt() || field->Type->Size != 4)
+				{
+					Error(p, "Variable %s in %s must have a size of 4 bytes for use as flag storage", referenced.GetChars(), type->TypeName.GetChars());
+				}
 			}
+			else field = nullptr;
 
 
 			FString qualifiedname;
@@ -1498,7 +1502,7 @@ bool ZCCCompiler::CompileFlagDefs(PClass *type, TArray<ZCC_FlagDef *> &Propertie
 				}
 			}
 
-			if (p->BitValue >= 0)
+			if (field != nullptr)
 				type->VMType->AddNativeField(FStringf("b%s", name.GetChars()), TypeSInt32, field->Offset, 0, 1 << p->BitValue);
 		} 
 	}
diff --git a/wadsrc/static/zscript/inventory/weapons.txt b/wadsrc/static/zscript/inventory/weapons.txt
index eabe72292f..add0409124 100644
--- a/wadsrc/static/zscript/inventory/weapons.txt
+++ b/wadsrc/static/zscript/inventory/weapons.txt
@@ -80,10 +80,10 @@ class Weapon : StateProvider
 	flagdef CheatNotWeapon: WeaponFlags, 18;	// Give cheat considers this not a weapon (used by Sigil)
 
 	// no-op flags
-	flagdef NoLMS: WeaponFlags, -1;
-	flagdef Allow_With_Respawn_Invul: WeaponFlags, -1;
-	flagdef BFG: WeaponFlags, -1;
-	flagdef Explosive: WeaponFlags, -1;
+	flagdef NoLMS: none, 0;
+	flagdef Allow_With_Respawn_Invul: none, 0;
+	flagdef BFG: none, 0;
+	flagdef Explosive: none, 0;
 
 	Default
 	{