diff --git a/dlls/gdi32/enhmfdrv/init.c b/dlls/gdi32/enhmfdrv/init.c
index c31496b6606..09af117e3ed 100644
--- a/dlls/gdi32/enhmfdrv/init.c
+++ b/dlls/gdi32/enhmfdrv/init.c
@@ -32,7 +32,7 @@
 
 WINE_DEFAULT_DEBUG_CHANNEL(enhmetafile);
 
-static BOOL EMFDRV_DeleteDC( PHYSDEV dev );
+static BOOL CDECL EMFDRV_DeleteDC( PHYSDEV dev );
 
 static const DC_FUNCTIONS EMFDRV_Funcs =
 {
@@ -161,7 +161,7 @@ static const DC_FUNCTIONS EMFDRV_Funcs =
 /**********************************************************************
  *	     EMFDRV_DeleteDC
  */
-static BOOL EMFDRV_DeleteDC( PHYSDEV dev )
+static BOOL CDECL EMFDRV_DeleteDC( PHYSDEV dev )
 {
     EMFDRV_PDEVICE *physDev = (EMFDRV_PDEVICE *)dev;
     UINT index;
diff --git a/dlls/gdi32/mfdrv/init.c b/dlls/gdi32/mfdrv/init.c
index 2cd3ff86a63..cee45347379 100644
--- a/dlls/gdi32/mfdrv/init.c
+++ b/dlls/gdi32/mfdrv/init.c
@@ -30,7 +30,7 @@
 
 WINE_DEFAULT_DEBUG_CHANNEL(metafile);
 
-static BOOL MFDRV_DeleteDC( PHYSDEV dev );
+static BOOL CDECL MFDRV_DeleteDC( PHYSDEV dev );
 
 static const DC_FUNCTIONS MFDRV_Funcs =
 {
@@ -205,7 +205,7 @@ static DC *MFDRV_AllocMetaFile(void)
 /**********************************************************************
  *	     MFDRV_DeleteDC
  */
-static BOOL MFDRV_DeleteDC( PHYSDEV dev )
+static BOOL CDECL MFDRV_DeleteDC( PHYSDEV dev )
 {
     METAFILEDRV_PDEVICE *physDev = (METAFILEDRV_PDEVICE *)dev;
     DWORD index;