[clang] [llvm] Replace autoconversion with TextEncodingConverter converters (PR #206519)

[Corentin Jabot via cfe-commits]

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@@ -610,8 +610,10 @@ static bool ParseDirective(StringRef S, ExpectedData *ED, SourceManager &SM,
           }
 
           FileID FID = SM.translateFile(*File);
+          // FIXME: Figure out character-encoding converter treatment.
           if (FID.isInvalid())
-            FID = SM.createFileID(*File, Pos, SrcMgr::C_User);
+            FID = SM.createFileID(*File, Pos, SrcMgr::C_User,
+                                  /*InputEncodingName=*/{});
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cor3ntin wrote:

That should use the input encoding.
However, you should consider that all clang own test files are utf8-ended and should not be converted.
So you might want to modify lit to force utf-8 for test files (of anything compiled with clang),
or document that if there is no tag set for the entiere llvm source tree, nothing will be expected to work.

https://github.com/llvm/llvm-project/pull/206519