[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, 1 insertions, 1 deletions

diff --git a/llvm/lib/Support/OptimizedStructLayout.cpp b/llvm/lib/Support/OptimizedStructLayout.cpp
index 19a93ed..6e9eacb 100644
--- a/llvm/lib/Support/OptimizedStructLayout.cpp
+++ b/llvm/lib/Support/OptimizedStructLayout.cpp
@@ -436,7 +436,7 @@ llvm::performOptimizedStructLayout(MutableArrayRef<Field> Fields) {
   // Phase 2: repeatedly add the best flexible-offset field until
   // they're all gone.
   while (!FlexibleFieldsByAlignment.empty()) {
-    bool Success = tryAddBestField(None);
+    bool Success = tryAddBestField(std::nullopt);
     assert(Success && "didn't find a field with no fixed limit?");
     (void) Success;
   }