Adjust a few things to avoid triggering warnings under MSVC

[folly.git] / folly / SharedMutex.h

diff --git a/folly/SharedMutex.h b/folly/SharedMutex.h
index 24bce0d7c73a9b8328836bb23cd9d3c7eaf811b6..49dd29c64a3c65929e93ea5dad2e4be85cb386e7 100644 (file)
--- a/folly/SharedMutex.h
+++ b/folly/SharedMutex.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2016 Facebook, Inc.
+ * Copyright 2017 Facebook, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -765,7 +765,7 @@ class SharedMutexImpl {
       }
 
       uint32_t after = (state & kMayDefer) == 0 ? 0 : kPrevDefer;
-      if (!ReaderPriority || (state & (kMayDefer | kHasS)) == 0) {
+      if (!kReaderPriority || (state & (kMayDefer | kHasS)) == 0) {
         // Block readers immediately, either because we are in write
         // priority mode or because we can acquire the lock in one
         // step.  Note that if state has kHasU, then we are doing an
@@ -806,7 +806,7 @@ class SharedMutexImpl {
             return false;
           }
 
-          if (ReaderPriority && (state & kHasE) == 0) {
+          if (kReaderPriority && (state & kHasE) == 0) {
             assert((state & kBegunE) != 0);
             if (!state_.compare_exchange_strong(state,
                                                 (state & ~kBegunE) | kHasE)) {
@@ -1390,7 +1390,7 @@ bool SharedMutexImpl<ReaderPriority, Tag_, Atom, BlockImmediately>::
       return false;
     }
 
-    uint32_t slot;
+    uint32_t slot = tls_lastDeferredReaderSlot;
     uintptr_t slotValue = 1; // any non-zero value will do
 
     bool canAlreadyDefer = (state & kMayDefer) != 0;
@@ -1399,7 +1399,6 @@ bool SharedMutexImpl<ReaderPriority, Tag_, Atom, BlockImmediately>::
     bool drainInProgress = ReaderPriority && (state & kBegunE) != 0;
     if (canAlreadyDefer || (aboveDeferThreshold && !drainInProgress)) {
       /* Try using the most recent slot first. */
-      slot = tls_lastDeferredReaderSlot;
       slotValue = deferredReader(slot)->load(std::memory_order_relaxed);
       if (slotValue != 0) {
         // starting point for our empty-slot search, can change after