Bug 1010634, Part 2: Fix compiler warnings in MFBT and XPCOM, r=ehsan

--HG--
extra : rebase_source : 8839297479ce2ade7a7e6cb5099178e799a0e516

mfbt/MathAlgorithms.h

@@ -205,7 +205,7 @@ namespace detail {
     uint32_t hi = uint32_t(u >> 32);
     if (hi != 0)
       return CountLeadingZeroes32(hi);
-    return 32 + CountLeadingZeroes32(uint32_t(u));
+    return 32u + CountLeadingZeroes32(uint32_t(u));
 #  endif
   }
 
@@ -220,7 +220,7 @@ namespace detail {
     uint32_t lo = uint32_t(u);
     if (lo != 0)
       return CountTrailingZeroes32(lo);
-    return 32 + CountTrailingZeroes32(uint32_t(u >> 32));
+    return 32u + CountTrailingZeroes32(uint32_t(u >> 32));
 #  endif
   }
 
@@ -351,7 +351,7 @@ class CeilingLog2<T, 4>
   public:
     static uint_fast8_t compute(const T t) {
       // Check for <= 1 to avoid the == 0 undefined case.
-      return t <= 1 ? 0 : 32 - CountLeadingZeroes32(t - 1);
+      return t <= 1 ? 0u : 32u - CountLeadingZeroes32(t - 1);
     }
 };
 
@@ -400,7 +400,7 @@ class FloorLog2<T, 4>
 {
   public:
     static uint_fast8_t compute(const T t) {
-      return 31 - CountLeadingZeroes32(t | 1);
+      return 31u - CountLeadingZeroes32(t | 1);
     }
 };
 
@@ -409,7 +409,7 @@ class FloorLog2<T, 8>
 {
   public:
     static uint_fast8_t compute(const T t) {
-      return 63 - CountLeadingZeroes64(t | 1);
+      return 63u - CountLeadingZeroes64(t | 1);
     }
 };
 

xpcom/glue/DeadlockDetector.h

@@ -227,7 +227,7 @@ private:
     }
     static PLHashNumber HashKey(const void* aKey)
     {
-        return NS_PTR_TO_INT32(aKey) >> 2;
+        return static_cast<PLHashNumber>(NS_PTR_TO_INT32(aKey) >> 2);
     }
     static const PLHashAllocOps kAllocOps;
 

xpcom/glue/nsTArray.h

@@ -751,9 +751,7 @@ public:
 
   // A special value that is used to indicate an invalid or unknown index
   // into the array.
-  enum {
-    NoIndex = index_type(-1)
-  };
+  static const index_type NoIndex = index_type(-1);
 
   using base_type::Length;
 

xpcom/string/public/nsCharTraits.h

@@ -162,7 +162,7 @@ struct nsCharTraits<char16_t>
   {
     for (char_type* s = aStr1; aN--; ++s, ++aStr2) {
       NS_ASSERTION(!(*aStr2 & ~0x7F), "Unexpected non-ASCII character");
-      *s = *aStr2;
+      *s = static_cast<char_type>(*aStr2);
     }
     return aStr1;
   }
@@ -194,8 +194,10 @@ struct nsCharTraits<char16_t>
   {
     for (; aN--; ++aStr1, ++aStr2) {
       NS_ASSERTION(!(*aStr2 & ~0x7F), "Unexpected non-ASCII character");
-      if (!eq_int_type(to_int_type(*aStr1), to_int_type(*aStr2))) {
-        return to_int_type(*aStr1) - to_int_type(*aStr2);
+      if (!eq_int_type(to_int_type(*aStr1),
+                       to_int_type(static_cast<char_type>(*aStr2)))) {
+        return to_int_type(*aStr1) -
+               to_int_type(static_cast<char_type>(*aStr2));
       }
     }
 
@@ -214,8 +216,10 @@ struct nsCharTraits<char16_t>
         return 1;
       }
       NS_ASSERTION(!(*aStr2 & ~0x7F), "Unexpected non-ASCII character");
-      if (!eq_int_type(to_int_type(*aStr1), to_int_type(*aStr2))) {
-        return to_int_type(*aStr1) - to_int_type(*aStr2);
+      if (!eq_int_type(to_int_type(*aStr1),
+                       to_int_type(static_cast<char_type>(*aStr2)))) {
+        return to_int_type(*aStr1) -
+               to_int_type(static_cast<char_type>(*aStr2));
       }
     }
 
@@ -248,8 +252,9 @@ struct nsCharTraits<char16_t>
       NS_ASSERTION(!(*aStr2 >= 'A' && *aStr2 <= 'Z'),
                    "Unexpected uppercase character");
       char_type lower_s1 = ASCIIToLower(*aStr1);
-      if (lower_s1 != to_char_type(*aStr2)) {
-        return to_int_type(lower_s1) - to_int_type(*aStr2);
+      if (lower_s1 != static_cast<char_type>(*aStr2)) {
+        return to_int_type(lower_s1) -
+               to_int_type(static_cast<char_type>(*aStr2));
       }
     }
 
@@ -271,8 +276,9 @@ struct nsCharTraits<char16_t>
       NS_ASSERTION(!(*aStr2 >= 'A' && *aStr2 <= 'Z'),
                    "Unexpected uppercase character");
       char_type lower_s1 = ASCIIToLower(*aStr1);
-      if (lower_s1 != to_char_type(*aStr2)) {
-        return to_int_type(lower_s1) - to_int_type(*aStr2);
+      if (lower_s1 != static_cast<char_type>(*aStr2)) {
+        return to_int_type(lower_s1) -
+               to_int_type(static_cast<char_type>(*aStr2));
       }
     }
 

xpcom/string/public/nsReadableUtils.h

@@ -13,6 +13,7 @@
  * According to our conventions, they should be |NS_xxx|.
  */
 
+#include "mozilla/Assertions.h"
 #include "nsAString.h"
 
 #include "nsTArrayForwardDeclare.h"
@@ -21,13 +22,15 @@ inline size_t
 Distance(const nsReadingIterator<char16_t>& aStart,
          const nsReadingIterator<char16_t>& aEnd)
 {
-  return aEnd.get() - aStart.get();
+  MOZ_ASSERT(aStart.get() <= aEnd.get());
+  return static_cast<size_t>(aEnd.get() - aStart.get());
 }
 inline size_t
 Distance(const nsReadingIterator<char>& aStart,
          const nsReadingIterator<char>& aEnd)
 {
-  return aEnd.get() - aStart.get();
+  MOZ_ASSERT(aStart.get() <= aEnd.get());
+  return static_cast<size_t>(aEnd.get() - aStart.get());
 }
 
 void LossyCopyUTF16toASCII(const nsAString& aSource, nsACString& aDest);