Fix cast in CacheMemoryMonitor (dotnet/corefx#41776)

Avoid overflow.

Commit migrated from https://github.com/dotnet/corefx/commit/6b2cb3a16a717b47c72c088d073a8f598bfc9335

diff --git a/src/libraries/System.Runtime.Caching/src/System/Runtime/Caching/CacheMemoryMonitor.cs b/src/libraries/System.Runtime.Caching/src/System/Runtime/Caching/CacheMemoryMonitor.cs
index f9e6727..5187c44 100644 (file)
--- a/src/libraries/System.Runtime.Caching/src/System/Runtime/Caching/CacheMemoryMonitor.cs
+++ b/src/libraries/System.Runtime.Caching/src/System/Runtime/Caching/CacheMemoryMonitor.cs
@@ -235,7 +235,7 @@ namespace System.Runtime.Caching
 
         internal void SetLimit(int cacheMemoryLimitMegabytes)
         {
-            long cacheMemoryLimit = cacheMemoryLimitMegabytes << MEGABYTE_SHIFT;
+            long cacheMemoryLimit = ((long)cacheMemoryLimitMegabytes) << MEGABYTE_SHIFT;
             _memoryLimit = cacheMemoryLimit != 0 ?
                 cacheMemoryLimit :
                 EffectiveProcessMemoryLimit;