Revert D4310312: [Folly] Enable -Wunreachable-code

[folly.git] / folly / FBVector.h

diff --git a/folly/FBVector.h b/folly/FBVector.h
index 6c6de44e2d7768e1ae6fff642bb781ba82ffc0f0..1bcc76513a793e42534756a176e9fe1784cfe16f 100644 (file)
--- a/folly/FBVector.h
+++ b/folly/FBVector.h
@@ -149,7 +149,7 @@ private:
           S_destroy_range_a(*this, b_, e_);
         }
 
-        D_deallocate(b_, z_ - b_);
+        D_deallocate(b_, size_type(z_ - b_));
       }
     }
 
@@ -430,7 +430,9 @@ private:
   // optimized
   static void S_uninitialized_fill_n(T* dest, size_type n) {
     if (folly::IsZeroInitializable<T>::value) {
-      std::memset(dest, 0, sizeof(T) * n);
+      if (LIKELY(n != 0)) {
+        std::memset(dest, 0, sizeof(T) * n);
+      }
     } else {
       auto b = dest;
       auto e = dest + n;
@@ -913,7 +915,7 @@ public:
 public:
 
   size_type size() const noexcept {
-    return impl_.e_ - impl_.b_;
+    return size_type(impl_.e_ - impl_.b_);
   }
 
   size_type max_size() const noexcept {
@@ -944,7 +946,7 @@ public:
   }
 
   size_type capacity() const noexcept {
-    return impl_.z_ - impl_.b_;
+    return size_type(impl_.z_ - impl_.b_);
   }
 
   bool empty() const noexcept {
@@ -964,7 +966,7 @@ public:
       throw;
     }
     if (impl_.b_)
-      M_deallocate(impl_.b_, impl_.z_ - impl_.b_);
+      M_deallocate(impl_.b_, size_type(impl_.z_ - impl_.b_));
     impl_.z_ = newB + newCap;
     impl_.e_ = newB + (impl_.e_ - impl_.b_);
     impl_.b_ = newB;