--- a/image/decoders/nsPNGDecoder.cpp
+++ b/image/decoders/nsPNGDecoder.cpp
@@ -282,17 +282,17 @@ nsPNGDecoder::WriteInternal(const char *
   // If we only want width/height, we don't need to go through libpng
   if (IsSizeDecode()) {
 
     // Are we done?
     if (mHeaderBytesRead == BYTES_NEEDED_FOR_DIMENSIONS)
       return;
 
     // Scan the header for the width and height bytes
-    PRUint32 pos = 0;
+    uint32_t pos = 0;
     const uint8_t *bptr = (uint8_t *)aBuffer;
 
     while (pos < aCount && mHeaderBytesRead < BYTES_NEEDED_FOR_DIMENSIONS) {
       // Verify the signature bytes
       if (mHeaderBytesRead < sizeof(pngSignatureBytes)) {
         if (bptr[pos] != nsPNGDecoder::pngSignatureBytes[mHeaderBytesRead]) {
           PostDataError();
           return;
@@ -307,18 +307,18 @@ nsPNGDecoder::WriteInternal(const char *
       pos ++;
       mHeaderBytesRead ++;
     }
 
     // If we're done now, verify the data and set up the container
     if (mHeaderBytesRead == BYTES_NEEDED_FOR_DIMENSIONS) {
 
       // Grab the width and height, accounting for endianness (thanks libpng!)
-      PRUint32 width = png_get_uint_32(mSizeBytes);
-      PRUint32 height = png_get_uint_32(mSizeBytes + 4);
+      uint32_t width = png_get_uint_32(mSizeBytes);
+      uint32_t height = png_get_uint_32(mSizeBytes + 4);
 
       // Too big?
       if ((width > MOZ_PNG_MAX_DIMENSION) || (height > MOZ_PNG_MAX_DIMENSION)) {
         PostDataError();
         return;
       }
 
       // Post our size to the superclass

--- a/image/decoders/nsPNGDecoder.h
+++ b/image/decoders/nsPNGDecoder.h
@@ -74,18 +74,18 @@ public:
   uint8_t *mCMSLine;
   uint8_t *interlacebuf;
   qcms_profile *mInProfile;
   qcms_transform *mTransform;
 
   gfxASurface::gfxImageFormat format;
 
   // For size decodes
-  PRUint8  mSizeBytes[8]; // Space for width and height, both 4 bytes
-  PRUint32 mHeaderBytesRead;
+  uint8_t mSizeBytes[8]; // Space for width and height, both 4 bytes
+  uint32_t mHeaderBytesRead;
 
   // whether CMS or premultiplied alpha are forced off
   uint32_t mCMSMode;
 
   uint8_t mChannels;
   bool mFrameHasNoAlpha;
   bool mFrameIsHidden;
   bool mDisablePremultipliedAlpha;