diff --git a/gfx/src/gtk/nsFontMetricsGTK.cpp b/gfx/src/gtk/nsFontMetricsGTK.cpp
index 5e1163ee932..cd57245aa8c 100644
--- a/gfx/src/gtk/nsFontMetricsGTK.cpp
+++ b/gfx/src/gtk/nsFontMetricsGTK.cpp
@@ -137,8 +137,8 @@ struct nsFontFamily
 
 struct nsFontFamilyName
 {
-  char* mName;
-  char* mXName;
+  const char* mName;
+  const char* mXName;
 };
 
 struct nsFontPropertyName
@@ -1045,7 +1045,7 @@ InitGlobals(nsIDeviceContext *aDevice)
   nsFontFamilyName* f = gFamilyNameTable;
   while (f->mName) {
     nsCStringKey key(f->mName);
-    gAliases->Put(&key, f->mXName);
+    gAliases->Put(&key, (void *)f->mXName);
     f++;
   }
   gWeights = new nsHashtable();
@@ -3174,11 +3174,13 @@ nsFontMetricsGTK::PickASizeAndLoad(nsFontStretch* aStretch,
   return AddToLoadedFontsList(font);
 }
 
+PR_BEGIN_EXTERN_C
 static int
 CompareSizes(const void* aArg1, const void* aArg2, void *data)
 {
   return (*((nsFontGTK**) aArg1))->mSize - (*((nsFontGTK**) aArg2))->mSize;
 }
+PR_END_EXTERN_C
 
 void
 nsFontStretch::SortSizes(void)
@@ -4953,6 +4955,7 @@ EnumerateNode(void* aElement, void* aData)
   return PR_TRUE; // continue
 }
 
+PR_BEGIN_EXTERN_C
 static int
 CompareFontNames(const void* aArg1, const void* aArg2, void* aClosure)
 {
@@ -4963,6 +4966,7 @@ CompareFontNames(const void* aArg1, const void* aArg2, void* aClosure)
 
   return nsCRT::strcmp(str1, str2);
 }
+PR_END_EXTERN_C
 
 static nsresult
 EnumFonts(nsIAtom* aLangGroup, const char* aGeneric, PRUint32* aCount,
diff --git a/gfx/src/xlib/nsFontMetricsXlib.cpp b/gfx/src/xlib/nsFontMetricsXlib.cpp
index cfcefc4f4bf..3e7298f58a0 100644
--- a/gfx/src/xlib/nsFontMetricsXlib.cpp
+++ b/gfx/src/xlib/nsFontMetricsXlib.cpp
@@ -110,7 +110,9 @@ static PRLogModuleInfo *FontMetricsXlibLM = PR_NewLogModule("FontMetricsXlib");
 
 /* Local prototypes */
 static PRBool                 FreeNode(nsHashKey* aKey, void* aData, void* aClosure);
+#ifdef USE_FREETYPE
 static void                   CharSetNameToCodeRangeBits(const char*, PRUint32*, PRUint32*);
+#endif /* USE_FREETYPE */
 static nsFontCharSetMapXlib  *GetCharSetMap(const char *aCharSetName);
 
 // the font catalog is so expensive to generate
@@ -222,14 +224,16 @@ static PRInt32 gBitmapScaleMinimum = 10;
 static double  gBitmapOversize = 1.2;
 static double  gBitmapUndersize = 0.8;
 
+#ifdef USE_AASB
 static PRInt32 gAntiAliasMinimum = 8;
+#endif /* USE_AASB */
 static PRInt32 gEmbeddedBitmapMaximumHeight = 1000000;
 
-#ifdef USE_FREETYOE
+#ifdef USE_FREETYPE
 static PRBool  gEnableFreeType2 = PR_TRUE;
 static PRBool  gFreeType2Autohinted = PR_FALSE;
 static PRBool  gFreeType2Unhinted = PR_TRUE;
-#endif /* USE_FREETYOE */
+#endif /* USE_FREETYPE */
 #ifdef USE_AASB
 static PRUint8 gAATTDarkTextMinValue = 64;
 static double  gAATTDarkTextGain = 0.8;
@@ -3262,7 +3266,9 @@ nsFontMetricsXlib::PickASizeAndLoad(nsFontStretchXlib* aStretch,
 
   PRBool      use_scaled_font               = PR_FALSE;
   PRBool      have_nearly_rightsized_bitmap = PR_FALSE;
+#ifdef USE_AASB
   nsFontXlib *base_aafont                   = nsnull;
+#endif /* USE_AASB */
 
 #ifdef USE_XPRINT
 #define ALWAYS_USE_SCALED_FONTS_FOR_XPRINT 1
@@ -3463,11 +3469,13 @@ nsFontMetricsXlib::PickASizeAndLoad(nsFontStretchXlib* aStretch,
   return AddToLoadedFontsList(font);
 }
 
+PR_BEGIN_EXTERN_C
 static int
 CompareSizes(const void* aArg1, const void* aArg2, void *data)
 {
   return (*((nsFontXlib**) aArg1))->mSize - (*((nsFontXlib**) aArg2))->mSize;
 }
+PR_END_EXTERN_C
 
 void
 nsFontStretchXlib::SortSizes(void)
@@ -5340,6 +5348,7 @@ EnumerateNode(void* aElement, void* aData)
   return PR_TRUE; // continue
 }
 
+PR_BEGIN_EXTERN_C
 static int
 CompareFontNames(const void* aArg1, const void* aArg2, void* aClosure)
 {
@@ -5350,6 +5359,7 @@ CompareFontNames(const void* aArg1, const void* aArg2, void* aClosure)
 
   return nsCRT::strcmp(str1, str2);
 }
+PR_END_EXTERN_C
 
 static nsresult
 EnumFonts(nsIAtom* aLangGroup, const char* aGeneric, PRUint32* aCount,
@@ -5441,6 +5451,7 @@ nsFontCharSetMapXlib *GetCharSetMap(const char *aCharSetName)
   return charSetMap;
 }
 
+#ifdef USE_FREETYPE
 static
 void CharSetNameToCodeRangeBits(const char *aCharset,
                                 PRUint32 *aCodeRange1, PRUint32 *aCodeRange2)
@@ -5451,4 +5462,5 @@ void CharSetNameToCodeRangeBits(const char *aCharset,
   *aCodeRange1 = charSetInfo->mCodeRange1Bits;
   *aCodeRange2 = charSetInfo->mCodeRange2Bits;
 }
+#endif /* USE_FREETYPE */
 
diff --git a/gfx/src/xlib/nsRenderingContextXlib.cpp b/gfx/src/xlib/nsRenderingContextXlib.cpp
index 4303647df02..7534f8ee891 100644
--- a/gfx/src/xlib/nsRenderingContextXlib.cpp
+++ b/gfx/src/xlib/nsRenderingContextXlib.cpp
@@ -440,7 +440,6 @@ nsRenderingContextXlib::SetClipRect(const nsRect& aRect, nsClipCombine aCombine,
 {
   PR_LOG(RenderingContextXlibLM, PR_LOG_DEBUG, ("nsRenderingContextXlib::SetClipRect()\n"));
   nsRect trect = aRect;
-  Region rgn;
   mTranMatrix->TransformCoord(&trect.x, &trect.y,
                            &trect.width, &trect.height);
   switch(aCombine) {
@@ -482,7 +481,6 @@ NS_IMETHODIMP
 nsRenderingContextXlib::SetClipRegion(const nsIRegion& aRegion, nsClipCombine aCombine, PRBool &aClipState)
 {
   PR_LOG(RenderingContextXlibLM, PR_LOG_DEBUG, ("nsRenderingContextXlib::SetClipRegion()\n"));
-  Region rgn;
   switch(aCombine)
   {
     case nsClipCombine_kIntersect:
diff --git a/gfx/src/xlibrgb/xlibrgb.c b/gfx/src/xlibrgb/xlibrgb.c
index 0a14468f8aa..ff21e6732e6 100644
--- a/gfx/src/xlibrgb/xlibrgb.c
+++ b/gfx/src/xlibrgb/xlibrgb.c
@@ -3973,8 +3973,7 @@ xxlib_rgb_ditherable (XlibRgbHandle *handle)
 Colormap
 xxlib_rgb_get_cmap (XlibRgbHandle *handle)
 {
-  /* xxlib_rgb_init (); */
-  return (handle)?(handle->cmap):(NULL);
+  return (handle)?(handle->cmap):(None);
 }
 
 Visual *
@@ -4084,7 +4083,7 @@ Bool xxlib_register_handle(const char *name, XlibRgbHandle *handle)
 Bool xxlib_deregister_handle(const char *name)
 {
   RegisteredHandle *entry;
-  if (entry = xxlib_find_registered_handle(name))
+  if ((entry = xxlib_find_registered_handle(name)) != NULL)
   {
     free((void *)entry->name);
     entry->name   = NULL;
diff --git a/gfx/src/xprint/nsXPrintContext.cpp b/gfx/src/xprint/nsXPrintContext.cpp
index 0159dd0ac7c..9b6436a319e 100644
--- a/gfx/src/xprint/nsXPrintContext.cpp
+++ b/gfx/src/xprint/nsXPrintContext.cpp
@@ -389,7 +389,7 @@ nsresult nsXPrintContext::SetMediumSize(const char *aPaperName)
   char *s;
   
   /* Did we get a tray name and paper name (e.g. "manual/din-a4") ? */
-  if (s = strchr(paper_name, '/'))
+  if ((s = strchr(paper_name, '/')) != nsnull)
   {
     const char *tray_name;
     *s = '\0';
diff --git a/gfx/src/xprint/xprintutil.c b/gfx/src/xprint/xprintutil.c
index 5e9ab0011d1..b2cdd3499c0 100644
--- a/gfx/src/xprint/xprintutil.c
+++ b/gfx/src/xprint/xprintutil.c
@@ -787,7 +787,7 @@ XPPrinterList XpuGetPrinterList( const char *printer, int *res_list_count )
     {
       Display *pdpy;
       
-      if( pdpy = XOpenDisplay(display) )
+      if( (pdpy = XOpenDisplay(display)) != NULL )
       {
         XPPrinterList list;
         int           list_count;
diff --git a/gfx/src/xprint/xprintutil_printtofile.c b/gfx/src/xprint/xprintutil_printtofile.c
index 0a0e63d82ab..c181e0eab5c 100644
--- a/gfx/src/xprint/xprintutil_printtofile.c
+++ b/gfx/src/xprint/xprintutil_printtofile.c
@@ -44,14 +44,12 @@
 #include <prthread.h>
 #else
 #include <pthread.h>
-#endif
-#else
-#ifdef __sun
-#include <wait.h>
-#endif /* __sun */
+#endif /* XPU_USE_NSPR */
 #endif /* XPU_USE_THREADS */
 #include <unistd.h>
 #include <sys/time.h>
+#include <sys/types.h>
+#include <sys/wait.h>
 
 /* local prototypes */
 #ifdef DEBUG