[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/GraphWriter.cpp b/llvm/lib/Support/GraphWriter.cpp
index c28d4a0..57559ad 100644
--- a/llvm/lib/Support/GraphWriter.cpp
+++ b/llvm/lib/Support/GraphWriter.cpp
@@ -136,14 +136,14 @@ static bool ExecGraphViewer(StringRef ExecPath, std::vector<StringRef> &args,
                             StringRef Filename, bool wait,
                             std::string &ErrMsg) {
   if (wait) {
-    if (sys::ExecuteAndWait(ExecPath, args, None, {}, 0, 0, &ErrMsg)) {
+    if (sys::ExecuteAndWait(ExecPath, args, std::nullopt, {}, 0, 0, &ErrMsg)) {
       errs() << "Error: " << ErrMsg << "\n";
       return true;
     }
     sys::fs::remove(Filename);
     errs() << " done. \n";
   } else {
-    sys::ExecuteNoWait(ExecPath, args, None, {}, 0, &ErrMsg);
+    sys::ExecuteNoWait(ExecPath, args, std::nullopt, {}, 0, &ErrMsg);
     errs() << "Remember to erase graph file: " << Filename << "\n";
   }
   return false;