[llvm] Use std::nullopt instead of None (NFC)

This patch mechanically replaces None with std::nullopt where the
compiler would warn if None were deprecated.  The intent is to reduce
the amount of manual work required in migrating from Optional to
std::optional.

This is part of an effort to migrate from llvm::Optional to
std::optional:

https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716

1 files changed, 2 insertions, 2 deletions

diff --git a/llvm/lib/Support/LockFileManager.cpp b/llvm/lib/Support/LockFileManager.cpp
index 5fd5299..6e934ba 100644
--- a/llvm/lib/Support/LockFileManager.cpp
+++ b/llvm/lib/Support/LockFileManager.cpp
@@ -60,7 +60,7 @@ LockFileManager::readLockFile(StringRef LockFileName) {
       MemoryBuffer::getFile(LockFileName);
   if (!MBOrErr) {
     sys::fs::remove(LockFileName);
-    return None;
+    return std::nullopt;
   }
   MemoryBuffer &MB = *MBOrErr.get();
 
@@ -77,7 +77,7 @@ LockFileManager::readLockFile(StringRef LockFileName) {
 
   // Delete the lock file. It's invalid anyway.
   sys::fs::remove(LockFileName);
-  return None;
+  return std::nullopt;
 }
 
 static std::error_code getHostID(SmallVectorImpl<char> &HostID) {