diff --git a/src/d_dehacked.cpp b/src/d_dehacked.cpp
index d01e9513f..e6376a589 100644
--- a/src/d_dehacked.cpp
+++ b/src/d_dehacked.cpp
@@ -1755,21 +1755,21 @@ static int PatchCheats (int dummy)
 static int PatchMisc (int dummy)
 {
 	static const struct Key keys[] = {
-		{ "Initial Health",			myoffsetof(struct DehInfo,StartHealth) },
-		{ "Initial Bullets",		myoffsetof(struct DehInfo,StartBullets) },
-		{ "Max Health",				myoffsetof(struct DehInfo,MaxHealth) },
-		{ "Max Armor",				myoffsetof(struct DehInfo,MaxArmor) },
-		{ "Green Armor Class",		myoffsetof(struct DehInfo,GreenAC) },
-		{ "Blue Armor Class",		myoffsetof(struct DehInfo,BlueAC) },
-		{ "Max Soulsphere",			myoffsetof(struct DehInfo,MaxSoulsphere) },
-		{ "Soulsphere Health",		myoffsetof(struct DehInfo,SoulsphereHealth) },
-		{ "Megasphere Health",		myoffsetof(struct DehInfo,MegasphereHealth) },
-		{ "God Mode Health",		myoffsetof(struct DehInfo,GodHealth) },
-		{ "IDFA Armor",				myoffsetof(struct DehInfo,FAArmor) },
-		{ "IDFA Armor Class",		myoffsetof(struct DehInfo,FAAC) },
-		{ "IDKFA Armor",			myoffsetof(struct DehInfo,KFAArmor) },
-		{ "IDKFA Armor Class",		myoffsetof(struct DehInfo,KFAAC) },
-		{ "No Autofreeze",			myoffsetof(struct DehInfo,NoAutofreeze) },
+		{ "Initial Health",			static_cast<ptrdiff_t>(myoffsetof(struct DehInfo,StartHealth)) },
+		{ "Initial Bullets",		static_cast<ptrdiff_t>(myoffsetof(struct DehInfo,StartBullets)) },
+		{ "Max Health",				static_cast<ptrdiff_t>(myoffsetof(struct DehInfo,MaxHealth)) },
+		{ "Max Armor",				static_cast<ptrdiff_t>(myoffsetof(struct DehInfo,MaxArmor)) },
+		{ "Green Armor Class",		static_cast<ptrdiff_t>(myoffsetof(struct DehInfo,GreenAC)) },
+		{ "Blue Armor Class",		static_cast<ptrdiff_t>(myoffsetof(struct DehInfo,BlueAC)) },
+		{ "Max Soulsphere",			static_cast<ptrdiff_t>(myoffsetof(struct DehInfo,MaxSoulsphere)) },
+		{ "Soulsphere Health",		static_cast<ptrdiff_t>(myoffsetof(struct DehInfo,SoulsphereHealth)) },
+		{ "Megasphere Health",		static_cast<ptrdiff_t>(myoffsetof(struct DehInfo,MegasphereHealth)) },
+		{ "God Mode Health",		static_cast<ptrdiff_t>(myoffsetof(struct DehInfo,GodHealth)) },
+		{ "IDFA Armor",				static_cast<ptrdiff_t>(myoffsetof(struct DehInfo,FAArmor)) },
+		{ "IDFA Armor Class",		static_cast<ptrdiff_t>(myoffsetof(struct DehInfo,FAAC)) },
+		{ "IDKFA Armor",			static_cast<ptrdiff_t>(myoffsetof(struct DehInfo,KFAArmor)) },
+		{ "IDKFA Armor Class",		static_cast<ptrdiff_t>(myoffsetof(struct DehInfo,KFAAC)) },
+		{ "No Autofreeze",			static_cast<ptrdiff_t>(myoffsetof(struct DehInfo,NoAutofreeze)) },
 		{ NULL, 0 }
 	};
 	int result;
diff --git a/src/thingdef/thingdef.h b/src/thingdef/thingdef.h
index 08264e0a8..63d04ea29 100644
--- a/src/thingdef/thingdef.h
+++ b/src/thingdef/thingdef.h
@@ -354,11 +354,11 @@ int MatchString (const char *in, const char **strings);
 	MSVC_MSEG FVariableInfo *infoptr_GlobalDef__##name GCC_MSEG = &GlobalDef__##name;
 
 #define DEFINE_MEMBER_VARIABLE(name, cls) \
-	static FVariableInfo GlobalDef__##name = { #name, myoffsetof(cls, name), RUNTIME_CLASS(cls) }; \
+	static FVariableInfo GlobalDef__##name = { #name, static_cast<intptr_t>(myoffsetof(cls, name)), RUNTIME_CLASS(cls) }; \
 	MSVC_MSEG FVariableInfo *infoptr_GlobalDef__##name GCC_MSEG = &GlobalDef__##name;
 
 #define DEFINE_MEMBER_VARIABLE_ALIAS(name, alias, cls) \
-	static FVariableInfo GlobalDef__##name = { #name, myoffsetof(cls, alias), RUNTIME_CLASS(cls) }; \
+	static FVariableInfo GlobalDef__##name = { #name, static_cast<intptr_t>(myoffsetof(cls, alias)), RUNTIME_CLASS(cls) }; \
 	MSVC_MSEG FVariableInfo *infoptr_GlobalDef__##name GCC_MSEG = &GlobalDef__##name;