[clangd] Fix modernize-loop-convert "multiple diag in flight" crash.

Summary:
this maybe not ideal, but it is trivial and does fix the crash.

Fixes https://github.com/clangd/clangd/issues/156.

Reviewers: sammccall

Subscribers: ilya-biryukov, MaskRay, jkorous, arphaman, kadircet, usaxena95, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D78715

(cherry picked from commit a466e4be3831848d7ff6ffbe4f57d99de8fb66af)

1 files changed, 8 insertions, 9 deletions

diff --git a/clang-tools-extra/clang-tidy/modernize/LoopConvertCheck.cpp b/clang-tools-extra/clang-tidy/modernize/LoopConvertCheck.cpp
index f359702b3f5..01a6ca74898 100644
--- a/clang-tools-extra/clang-tidy/modernize/LoopConvertCheck.cpp
+++ b/clang-tools-extra/clang-tidy/modernize/LoopConvertCheck.cpp
@@ -522,13 +522,11 @@ void LoopConvertCheck::doConversion(
     const ValueDecl *MaybeContainer, const UsageResult &Usages,
     const DeclStmt *AliasDecl, bool AliasUseRequired, bool AliasFromForInit,
     const ForStmt *Loop, RangeDescriptor Descriptor) {
-  auto Diag = diag(Loop->getForLoc(), "use range-based for loop instead");
-
   std::string VarName;
   bool VarNameFromAlias = (Usages.size() == 1) && AliasDecl;
   bool AliasVarIsRef = false;
   bool CanCopy = true;
-
+  std::vector<FixItHint> FixIts;
   if (VarNameFromAlias) {
     const auto *AliasVar = cast<VarDecl>(AliasDecl->getSingleDecl());
     VarName = AliasVar->getName().str();
@@ -560,8 +558,8 @@ void LoopConvertCheck::doConversion(
       getAliasRange(Context->getSourceManager(), ReplaceRange);
     }
 
-    Diag << FixItHint::CreateReplacement(
-        CharSourceRange::getTokenRange(ReplaceRange), ReplacementText);
+    FixIts.push_back(FixItHint::CreateReplacement(
+        CharSourceRange::getTokenRange(ReplaceRange), ReplacementText));
     // No further replacements are made to the loop, since the iterator or index
     // was used exactly once - in the initialization of AliasVar.
   } else {
@@ -606,8 +604,8 @@ void LoopConvertCheck::doConversion(
             Usage.Kind == Usage::UK_CaptureByCopy ? "&" + VarName : VarName;
       }
       TUInfo->getReplacedVars().insert(std::make_pair(Loop, IndexVar));
-      Diag << FixItHint::CreateReplacement(
-          CharSourceRange::getTokenRange(Range), ReplaceText);
+      FixIts.push_back(FixItHint::CreateReplacement(
+          CharSourceRange::getTokenRange(Range), ReplaceText));
     }
   }
 
@@ -645,8 +643,9 @@ void LoopConvertCheck::doConversion(
   std::string Range = ("(" + TypeString + " " + VarName + " : " +
                        MaybeDereference + Descriptor.ContainerString + ")")
                           .str();
-  Diag << FixItHint::CreateReplacement(
-      CharSourceRange::getTokenRange(ParenRange), Range);
+  FixIts.push_back(FixItHint::CreateReplacement(
+      CharSourceRange::getTokenRange(ParenRange), Range));
+  diag(Loop->getForLoc(), "use range-based for loop instead") << FixIts;
   TUInfo->getGeneratedDecls().insert(make_pair(Loop, VarName));
 }