diff --git a/composite/compalloc.c b/composite/compalloc.c
index fa092f489c..7761b3abf0 100644
--- a/composite/compalloc.c
+++ b/composite/compalloc.c
@@ -266,14 +266,14 @@ compFreeClientWindow(WindowPtr pWin, XID id)
 {
     ScreenPtr pScreen = pWin->drawable.pScreen;
     CompWindowPtr cw = GetCompWindow(pWin);
-    CompClientWindowPtr ccw, *prev;
     Bool anyMarked = FALSE;
     WindowPtr pLayerWin;
     PixmapPtr pPixmap = NULL;
 
     if (!cw)
         return;
-    for (prev = &cw->clients; (ccw = *prev); prev = &ccw->next) {
+    for (CompClientWindowPtr *prev = &cw->clients, ccw;
+                    (ccw = *prev); prev = &ccw->next) {
         if (ccw->id == id) {
             *prev = ccw->next;
             if (ccw->update == CompositeRedirectManual)
@@ -325,14 +325,13 @@ int
 compUnredirectWindow(ClientPtr pClient, WindowPtr pWin, int update)
 {
     CompWindowPtr cw = GetCompWindow(pWin);
-    CompClientWindowPtr ccw;
 
     BUG_RETURN_VAL(!pClient, BadValue);
 
     if (!cw)
         return BadValue;
 
-    for (ccw = cw->clients; ccw; ccw = ccw->next)
+    for (CompClientWindowPtr ccw = cw->clients; ccw; ccw = ccw->next)
         if (ccw->update == update && dixClientIdForXID(ccw->id) == pClient->index) {
             FreeResource(ccw->id, X11_RESTYPE_NONE);
             return Success;
@@ -348,7 +347,6 @@ int
 compRedirectSubwindows(ClientPtr pClient, WindowPtr pWin, int update)
 {
     CompSubwindowsPtr csw = GetCompSubwindows(pWin);
-    WindowPtr pChild;
 
     /*
      * Only one Manual update is allowed
@@ -383,12 +381,12 @@ compRedirectSubwindows(ClientPtr pClient, WindowPtr pWin, int update)
     /*
      * Redirect all existing windows
      */
-    for (pChild = pWin->lastChild; pChild; pChild = pChild->prevSib) {
+    for (WindowPtr pChild = pWin->lastChild; pChild; pChild = pChild->prevSib) {
         int ret = compRedirectWindow(pClient, pChild, update);
 
         if (ret != Success) {
-            for (pChild = pChild->nextSib; pChild; pChild = pChild->nextSib)
-                (void) compUnredirectWindow(pClient, pChild, update);
+            for (WindowPtr pSib = pChild->nextSib; pSib; pSib = pSib->nextSib)
+                (void) compUnredirectWindow(pClient, pSib, update);
             if (!csw->clients) {
                 free(csw);
                 dixSetPrivate(&pWin->devPrivates, CompSubwindowsPrivateKey, 0);
@@ -424,12 +422,11 @@ void
 compFreeClientSubwindows(WindowPtr pWin, XID id)
 {
     CompSubwindowsPtr csw = GetCompSubwindows(pWin);
-    CompClientWindowPtr ccw, *prev;
-    WindowPtr pChild;
 
     if (!csw)
         return;
-    for (prev = &csw->clients; (ccw = *prev); prev = &ccw->next) {
+    for (CompClientWindowPtr *prev = &csw->clients, ccw;
+                    (ccw = *prev); prev = &ccw->next) {
         if (ccw->id == id) {
             ClientPtr pClient = dixClientForXID(id);
 
@@ -450,7 +447,8 @@ compFreeClientSubwindows(WindowPtr pWin, XID id)
             /*
              * Unredirect all existing subwindows
              */
-            for (pChild = pWin->lastChild; pChild; pChild = pChild->prevSib)
+            for (WindowPtr pChild = pWin->lastChild;
+                    pChild; pChild = pChild->prevSib)
                 (void) compUnredirectWindow(pClient, pChild, ccw->update);
 
             free(ccw);
@@ -475,11 +473,10 @@ int
 compUnredirectSubwindows(ClientPtr pClient, WindowPtr pWin, int update)
 {
     CompSubwindowsPtr csw = GetCompSubwindows(pWin);
-    CompClientWindowPtr ccw;
 
     if (!csw)
         return BadValue;
-    for (ccw = csw->clients; ccw; ccw = ccw->next)
+    for (CompClientWindowPtr ccw = csw->clients; ccw; ccw = ccw->next)
         if (ccw->update == update && dixClientIdForXID(ccw->id) == pClient->index) {
             FreeResource(ccw->id, X11_RESTYPE_NONE);
             return Success;
@@ -495,11 +492,10 @@ int
 compRedirectOneSubwindow(WindowPtr pParent, WindowPtr pWin)
 {
     CompSubwindowsPtr csw = GetCompSubwindows(pParent);
-    CompClientWindowPtr ccw;
 
     if (!csw)
         return Success;
-    for (ccw = csw->clients; ccw; ccw = ccw->next) {
+    for (CompClientWindowPtr ccw = csw->clients; ccw; ccw = ccw->next) {
         int ret = compRedirectWindow(dixClientForXID(ccw->id),
                                      pWin, ccw->update);
         if (ret != Success)
@@ -516,11 +512,10 @@ int
 compUnredirectOneSubwindow(WindowPtr pParent, WindowPtr pWin)
 {
     CompSubwindowsPtr csw = GetCompSubwindows(pParent);
-    CompClientWindowPtr ccw;
 
     if (!csw)
         return Success;
-    for (ccw = csw->clients; ccw; ccw = ccw->next) {
+    for (CompClientWindowPtr ccw = csw->clients; ccw; ccw = ccw->next) {
         int ret = compUnredirectWindow(dixClientForXID(ccw->id),
                                        pWin, ccw->update);
         if (ret != Success)
diff --git a/composite/compext.c b/composite/compext.c
index 22de9d7a25..acd2534194 100644
--- a/composite/compext.c
+++ b/composite/compext.c
@@ -400,18 +400,16 @@ GetCompositeWindowBytes(void *value, XID id, ResourceSizePtr size)
 void
 CompositeExtensionInit(void)
 {
-    ExtensionEntry *extEntry;
-
     /* Assume initialization is going to fail */
     noCompositeExtension = TRUE;
 
     for (unsigned int walkScreenIdx = 0; walkScreenIdx < screenInfo.numScreens; walkScreenIdx++) {
         ScreenPtr walkScreen = screenInfo.screens[walkScreenIdx];
-        VisualPtr vis;
 
         /* Composite on 8bpp pseudocolor root windows appears to fail, so
          * just disable it on anything pseudocolor for safety.
          */
+        VisualPtr vis;
         for (vis = walkScreen->visuals; vis->vid != walkScreen->rootVisual; vis++);
         if ((vis->class | DynamicClass) == PseudoColor)
             return;
@@ -451,7 +449,7 @@ CompositeExtensionInit(void)
             return;
     }
 
-    extEntry = AddExtension(COMPOSITE_NAME, 0, 0,
+    ExtensionEntry *extEntry = AddExtension(COMPOSITE_NAME, 0, 0,
                             ProcCompositeDispatch,
                             ProcCompositeDispatch,
                             NULL, StandardMinorOpcode);
diff --git a/composite/compinit.c b/composite/compinit.c
index 1844856e58..c29a896c12 100644
--- a/composite/compinit.c
+++ b/composite/compinit.c
@@ -93,9 +93,8 @@ compInstallColormap(ColormapPtr pColormap)
     VisualPtr pVisual = pColormap->pVisual;
     ScreenPtr pScreen = pColormap->pScreen;
     CompScreenPtr cs = GetCompScreen(pScreen);
-    int a;
 
-    for (a = 0; a < cs->numAlternateVisuals; a++)
+    for (int a = 0; a < cs->numAlternateVisuals; a++)
         if (pVisual->vid == cs->alternateVisuals[a])
             return;
     pScreen->InstallColormap = cs->InstallColormap;
@@ -160,9 +159,7 @@ compSourceValidate(DrawablePtr pDrawable,
 static DepthPtr
 compFindVisuallessDepth(ScreenPtr pScreen, int d)
 {
-    int i;
-
-    for (i = 0; i < pScreen->numDepths; i++) {
+    for (int i = 0; i < pScreen->numDepths; i++) {
         DepthPtr depth = &pScreen->allowedDepths[i];
 
         if (depth->depth == d) {
@@ -299,12 +296,12 @@ compAddAlternateVisual(ScreenPtr pScreen, CompScreenPtr cs,
 static Bool
 compAddAlternateVisuals(ScreenPtr pScreen, CompScreenPtr cs)
 {
-    int alt, ret = 0;
+    int ret = 0;
 
-    for (alt = 0; alt < ARRAY_SIZE(altVisuals); alt++)
+    for (int alt = 0; alt < ARRAY_SIZE(altVisuals); alt++)
         ret |= compAddAlternateVisual(pScreen, cs, altVisuals + alt);
 
-    return ! !ret;
+    return ret;
 }
 
 Bool
diff --git a/composite/compoverlay.c b/composite/compoverlay.c
index 13358d97ae..a976c5d8e0 100644
--- a/composite/compoverlay.c
+++ b/composite/compoverlay.c
@@ -59,9 +59,9 @@ compFreeOverlayClient(CompOverlayClientPtr pOcToDel)
 {
     ScreenPtr pScreen = pOcToDel->pScreen;
     CompScreenPtr cs = GetCompScreen(pScreen);
-    CompOverlayClientPtr *pPrev, pOc;
 
-    for (pPrev = &cs->pOverlayClients; (pOc = *pPrev); pPrev = &pOc->pNext) {
+    for (CompOverlayClientPtr *pPrev = &cs->pOverlayClients, pOc;
+                        (pOc = *pPrev); pPrev = &pOc->pNext) {
         if (pOc == pOcToDel) {
             *pPrev = pOc->pNext;
             free(pOc);
@@ -81,9 +81,9 @@ CompOverlayClientPtr
 compFindOverlayClient(ScreenPtr pScreen, ClientPtr pClient)
 {
     CompScreenPtr cs = GetCompScreen(pScreen);
-    CompOverlayClientPtr pOc;
 
-    for (pOc = cs->pOverlayClients; pOc != NULL; pOc = pOc->pNext)
+    for (CompOverlayClientPtr pOc = cs->pOverlayClients;
+                          pOc != NULL; pOc = pOc->pNext)
         if (pOc->pClient == pClient)
             return pOc;
 
diff --git a/composite/compwindow.c b/composite/compwindow.c
index 1d6f9b15ce..ca789654ff 100644
--- a/composite/compwindow.c
+++ b/composite/compwindow.c
@@ -320,9 +320,8 @@ Bool
 compIsAlternateVisual(ScreenPtr pScreen, XID visual)
 {
     CompScreenPtr cs = GetCompScreen(pScreen);
-    int i;
 
-    for (i = 0; cs && i < cs->numAlternateVisuals; i++)
+    for (int i = 0; cs && i < cs->numAlternateVisuals; i++)
         if (cs->alternateVisuals[i] == visual)
             return TRUE;
     return FALSE;
@@ -333,9 +332,8 @@ CompositeIsImplicitRedirectException(ScreenPtr pScreen,
                                      XID parentVisual, XID winVisual)
 {
     CompScreenPtr cs = GetCompScreen(pScreen);
-    int i;
 
-    for (i = 0; i < cs->numImplicitRedirectExceptions; i++)
+    for (int i = 0; i < cs->numImplicitRedirectExceptions; i++)
         if (cs->implicitRedirectExceptions[i].parentVisual == parentVisual &&
             cs->implicitRedirectExceptions[i].winVisual == winVisual)
             return TRUE;
@@ -564,14 +562,13 @@ compCreateWindow(WindowPtr pWin)
     ret = (*pScreen->CreateWindow) (pWin);
     if (pWin->parent && ret) {
         CompSubwindowsPtr csw = GetCompSubwindows(pWin->parent);
-        CompClientWindowPtr ccw;
         PixmapPtr parent_pixmap = (*pScreen->GetWindowPixmap)(pWin->parent);
         PixmapPtr window_pixmap = (*pScreen->GetWindowPixmap)(pWin);
 
         if (window_pixmap != parent_pixmap)
             (*pScreen->SetWindowPixmap) (pWin, parent_pixmap);
         if (csw)
-            for (ccw = csw->clients; ccw; ccw = ccw->next)
+            for (CompClientWindowPtr ccw = csw->clients; ccw; ccw = ccw->next)
                 compRedirectWindow(dixClientForXID(ccw->id),
                                    pWin, ccw->update);
         if (compImplicitRedirect(pWin, pWin->parent))
@@ -726,12 +723,10 @@ compPaintWindowToParent(WindowPtr pWin)
 void
 compPaintChildrenToWindow(WindowPtr pWin)
 {
-    WindowPtr pChild;
-
     if (!pWin->damagedDescendants)
         return;
 
-    for (pChild = pWin->lastChild; pChild; pChild = pChild->prevSib)
+    for (WindowPtr pChild = pWin->lastChild; pChild; pChild = pChild->prevSib)
         compPaintWindowToParent(pChild);
 
     pWin->damagedDescendants = FALSE;