diff --git a/kwin/libkwineffects/anidata.cpp b/kwin/libkwineffects/anidata.cpp
index 2e37632f..180ae648 100644
--- a/kwin/libkwineffects/anidata.cpp
+++ b/kwin/libkwineffects/anidata.cpp
@@ -38,7 +38,7 @@ AniData::AniData()
     waitAtSource = keepAtTarget = false;
 }
 
-AniData::AniData(AnimationEffect::Attribute a, int meta, int ms, const FPx2 &to,
+AniData::AniData(AnimationEffect::Attribute a, uint meta, int ms, const FPx2 &to,
                  QEasingCurve curve, int delay, const FPx2 &from, bool waitAtSource, bool keepAtTarget )
 {
     attribute = a;
diff --git a/kwin/libkwineffects/anidata_p.h b/kwin/libkwineffects/anidata_p.h
index 09b25a89..93a59cbb 100644
--- a/kwin/libkwineffects/anidata_p.h
+++ b/kwin/libkwineffects/anidata_p.h
@@ -30,7 +30,7 @@ namespace KWin {
 class AniData {
 public:
     AniData();
-    AniData(AnimationEffect::Attribute a, int meta, int ms, const FPx2 &to,
+    AniData(AnimationEffect::Attribute a, uint meta, int ms, const FPx2 &to,
             QEasingCurve curve, int delay, const FPx2 &from, bool waitAtSource, bool keepAtTarget = false);
     AniData(const AniData &other);
     inline void addTime(int t) { time += t; }
diff --git a/kwin/libkwineffects/kwinanimationeffect.cpp b/kwin/libkwineffects/kwinanimationeffect.cpp
index 172c870f..8493db47 100644
--- a/kwin/libkwineffects/kwinanimationeffect.cpp
+++ b/kwin/libkwineffects/kwinanimationeffect.cpp
@@ -634,7 +634,7 @@ float AnimationEffect::progress( const AniData &a ) const
     return 1.0; // we're done and "waiting" at the target value
 }
 
-int AnimationEffect::metaData( MetaType type, uint meta )
+uint AnimationEffect::metaData( MetaType type, uint meta )
 {
     switch (type) {
         case SourceAnchor:
diff --git a/kwin/libkwineffects/kwinanimationeffect.h b/kwin/libkwineffects/kwinanimationeffect.h
index c2b5d082..790be807 100644
--- a/kwin/libkwineffects/kwinanimationeffect.h
+++ b/kwin/libkwineffects/kwinanimationeffect.h
@@ -103,8 +103,10 @@ public:
         Position, Size, Translation, Clip, Generic, CrossFadePrevious,
         NonFloatBase = Position
     };
-    enum MetaType { SourceAnchor, TargetAnchor,
-                    RelativeSourceX, RelativeSourceY, RelativeTargetX, RelativeTargetY, Axis };
+    enum MetaType {
+        SourceAnchor = 0, TargetAnchor,
+        RelativeSourceX, RelativeSourceY, RelativeTargetX, RelativeTargetY, Axis
+    };
     /**
      * Whenever you intend to connect to the EffectsHandler::windowClosed() signal, do so when reimplementing the constructor.
      * Do *not* add private slots named _windowClosed( EffectWindow* w ) or _windowDeleted( EffectWindow* w ) !!
@@ -120,7 +122,7 @@ public:
      * The first 24 bits are reserved for the AnimationEffect class - you can use the last 8 bits for custom hints.
      * In case you transform a Generic attribute, all 32 bits are yours and you can use them as you want and read them in your genericAnimation() implementation.
      */
-    static int metaData(MetaType type, uint meta );
+    static uint metaData(MetaType type, uint meta );
     static void setMetaData(MetaType type, uint value, uint &meta );
 
     /**