[IR] Fixed ambiguous call to llvm::report_fatal_error

[slydiman]

Summary

This patch fixes the following error with MSVC 16.9.2:
llvm/lib/IR/GCStrategy.cpp(35): error C2668: 'llvm::report_fatal_error': ambiguous call to overloaded function
llvm/include/llvm/Support/ErrorHandling.h(75): note: could be 'void llvm::report_fatal_error(const llvm::Twine &,bool)'
llvm/include/llvm/Support/ErrorHandling.h(73): note: or 'void llvm::report_fatal_error(llvm::StringRef,bool)'
llvm/lib/IR/GCStrategy.cpp(35): note: while trying to match the argument list '(const std::string)'

[barannikov88]

llvm/lib/IR/GCStrategy.cpp

38

Please include the missing header. It is the reason why this error was not caught earlier.

[barannikov88]

llvm/lib/IR/GCStrategy.cpp

38

Sorry, the last part of my statement is not true. "Twine.h" seems to be transitively included from some other header, but not in all configurations.
"Twine.h" should be included now, because the class is directly used.

[barannikov88]

LGTM

[RKSimon]

LGTM

llvm/lib/IR/GCStrategy.cpp

 //===- GCStrategy.cpp - Garbage Collector Description ---------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
 // This file implements the policy object GCStrategy which describes the
 // behavior of a given garbage collector.
 //
 //===----------------------------------------------------------------------===//
 
 #include "llvm/IR/GCStrategy.h"
+#include "llvm/ADT/Twine.h"
 
 using namespace llvm;
 
 LLVM_INSTANTIATE_REGISTRY(GCRegistry)
 
 GCStrategy::GCStrategy() = default;
 
 std::unique_ptr<GCStrategy> llvm::getGCStrategy(const StringRef Name) {
   for (auto &S : GCRegistry::entries())
     if (S.getName() == Name)
       return S.instantiate();
 
   if (GCRegistry::begin() == GCRegistry::end()) {
     // In normal operation, the registry should not be empty.  There should
     // be the builtin GCs if nothing else.  The most likely scenario here is
     // that we got here without running the initializers used by the Registry
     // itself and it's registration mechanism.
     const std::string error =
         std::string("unsupported GC: ") + Name.str() +
         " (did you remember to link and initialize the library?)";
-    report_fatal_error(error);
+    report_fatal_error(Twine(error));
   } else
-    report_fatal_error(std::string("unsupported GC: ") + Name.str());
+    report_fatal_error(Twine(std::string("unsupported GC: ") + Name.str()));
 }