diff --git a/llvm/lib/ProfileData/SampleProfReader.cpp b/llvm/lib/ProfileData/SampleProfReader.cpp
index 1028c35..44547e3 100644
--- a/llvm/lib/ProfileData/SampleProfReader.cpp
+++ b/llvm/lib/ProfileData/SampleProfReader.cpp
@@ -749,7 +749,7 @@
   auto Buffer = std::move(BufferOrErr.get());
 
   // Sanity check the file.
-  if (Buffer->getBufferSize() > std::numeric_limits<uint32_t>::max())
+  if (uint64_t(Buffer->getBufferSize()) > std::numeric_limits<uint32_t>::max())
     return sampleprof_error::too_large;
 
   return std::move(Buffer);