diff --git a/format.cc b/format.cc
index a9577028..5f696799 100644
--- a/format.cc
+++ b/format.cc
@@ -444,7 +444,7 @@ class BasicArgFormatter : public ArgVisitor<Impl, void> {
     typedef typename BasicWriter<Char>::CharPtr CharPtr;
     Char fill = internal::CharTraits<Char>::cast(spec_.fill());
     CharPtr out = CharPtr();
-    const int CHAR_WIDTH = 1;
+    const unsigned CHAR_WIDTH = 1;
     if (spec_.width_ > CHAR_WIDTH) {
       out = writer_.grow_buffer(spec_.width_);
       if (spec_.align_ == ALIGN_RIGHT) {
diff --git a/format.h b/format.h
index 68c7e51b..29a7f0f2 100644
--- a/format.h
+++ b/format.h
@@ -292,7 +292,9 @@ class BasicStringRef {
   int compare(BasicStringRef other) const {
     std::size_t size = std::min(size_, other.size_);
     int result = std::char_traits<Char>::compare(data_, other.data_, size);
-    return result != 0 ? result : size_ - other.size_;
+    if (result == 0)
+      result = size_ == other.size_ ? 0 : (size_ < other.size_ ? -1 : 1);
+    return result;
   }
 
   friend bool operator==(BasicStringRef lhs, BasicStringRef rhs) {