diff --git a/dlls/x11drv/clipboard.c b/dlls/x11drv/clipboard.c
index 27fae3de70d..01d2c9748c0 100644
--- a/dlls/x11drv/clipboard.c
+++ b/dlls/x11drv/clipboard.c
@@ -1952,7 +1952,7 @@ static HANDLE X11DRV_CLIPBOARD_SerializeMetafile(INT wformat, HANDLE hdata, LPDW
                 memcpy(lpmfp, (LPVOID)hdata, sizeof(METAFILEPICT));
                 wiresize = *lpcbytes - sizeof(METAFILEPICT);
                 lpmfp->hMF = SetMetaFileBitsEx(wiresize,
-                    ((const char *)hdata) + sizeof(METAFILEPICT));
+                    ((const BYTE *)hdata) + sizeof(METAFILEPICT));
                 size = GetMetaFileBitsEx(lpmfp->hMF, 0, NULL);
                 GlobalUnlock(h);
             }
diff --git a/dlls/x11drv/xdnd.c b/dlls/x11drv/xdnd.c
index 7010b418435..f0b8c2a9c8e 100644
--- a/dlls/x11drv/xdnd.c
+++ b/dlls/x11drv/xdnd.c
@@ -111,7 +111,7 @@ void X11DRV_XDND_EnterEvent( HWND hWnd, XClientMessageEvent *event )
     else
     {
         count = 3;
-        xdndtypes = &event->data.l[2];
+        xdndtypes = (Atom*) &event->data.l[2];
     }
 
     if (TRACE_ON(xdnd))
diff --git a/dlls/x11drv/xfont.c b/dlls/x11drv/xfont.c
index 70e5e7f27c4..1a0d5aec1a0 100644
--- a/dlls/x11drv/xfont.c
+++ b/dlls/x11drv/xfont.c
@@ -3410,7 +3410,7 @@ BOOL X11DRV_GetCharWidth( X11DRV_PDEVICE *physDev, UINT firstChar, UINT lastChar
 		WCHAR wch = i;
 		BYTE ch;
 		UINT ch_f; /* character code in the font encoding */
-		WideCharToMultiByte( pfo->fi->codepage, 0, &wch, 1, &ch, 1, NULL, NULL );
+		WideCharToMultiByte( pfo->fi->codepage, 0, &wch, 1, (LPSTR)&ch, 1, NULL, NULL );
 		ch_f = ch;
 		if (ch_f >= pfo->fs->min_char_or_byte2 &&
 		    ch_f <= pfo->fs->max_char_or_byte2)
diff --git a/dlls/x11drv/xrandr.c b/dlls/x11drv/xrandr.c
index 138bf4d359a..b6e5805d074 100644
--- a/dlls/x11drv/xrandr.c
+++ b/dlls/x11drv/xrandr.c
@@ -78,7 +78,7 @@ static LPDDHALMODEINFO dd_modes;
 static unsigned int dd_mode_count;
 static XRRScreenSize *real_xrandr_sizes;
 static short **real_xrandr_rates;
-static unsigned int real_xrandr_sizes_count;
+static int real_xrandr_sizes_count;
 static int *real_xrandr_rates_count;
 static unsigned int real_xrandr_modes_count;
 
diff --git a/dlls/x11drv/xrender.c b/dlls/x11drv/xrender.c
index cd3aa12caf5..f27cca68ee0 100644
--- a/dlls/x11drv/xrender.c
+++ b/dlls/x11drv/xrender.c
@@ -702,7 +702,7 @@ static BOOL UploadGlyph(X11DRV_PDEVICE *physDev, int glyph, AA_Type format)
 	if(format == AA_None) {
 	    pitch = ((gi.width + 31) / 32) * 4;
 	    for(i = 0; i < gi.height; i++) {
-	        line = buf + i * pitch;
+	        line = (unsigned char*) buf + i * pitch;
 		output[0] = '\0';
 		for(j = 0; j < pitch * 8; j++) {
 	            strcat(output, (line[j / 8] & (1 << (7 - (j % 8)))) ? "#" : " ");
@@ -717,7 +717,7 @@ static BOOL UploadGlyph(X11DRV_PDEVICE *physDev, int glyph, AA_Type format)
 	    str[1] = '\0';
 	    pitch = ((gi.width + 3) / 4) * 4;
 	    for(i = 0; i < gi.height; i++) {
-	        line = buf + i * pitch;
+	        line = (unsigned char*) buf + i * pitch;
 		output[0] = '\0';
 		for(j = 0; j < pitch; j++) {
 		    str[0] = blks[line[j] >> 5];
@@ -731,7 +731,7 @@ static BOOL UploadGlyph(X11DRV_PDEVICE *physDev, int glyph, AA_Type format)
 
     if(formatEntry->glyphset) {
         if(format == AA_None && BitmapBitOrder(gdi_display) != MSBFirst) {
-	    unsigned char *byte = buf, c;
+	    unsigned char *byte = (unsigned char*) buf, c;
 	    int i = buflen;
 
 	    while(i--) {