[clang-tools-extra] [clang-tidy][NFC] Enable `modernize-use-auto` in clang-tidy config and fix warnings (PR #157468)

[via cfe-commits]

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@@ -138,9 +138,9 @@ void UseIntegerSignComparisonCheck::check(
     return;
   const Expr *SubExprLHS = nullptr;
   const Expr *SubExprRHS = nullptr;
-  SourceRange R1 = SourceRange(LHS->getBeginLoc());
-  SourceRange R2 = SourceRange(BinaryOp->getOperatorLoc());
-  SourceRange R3 = SourceRange(Lexer::getLocForEndOfToken(
+  SourceRange R1(LHS->getBeginLoc());
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flovent wrote:

This check correctly suggest `auto R1 = SourceRange(LHS->getBeginLoc());` here, but i think directly calling ctor is better here.

https://github.com/llvm/llvm-project/pull/157468