[clang] [Clang] Allow raw string literals in C as an extension (PR #88265)

[Owen Pan via cfe-commits]

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@@ -3850,6 +3850,7 @@ LangOptions getFormattingLangOpts(const FormatStyle &Style) {
   // the sequence "<::" will be unconditionally treated as "[:".
   // Cf. Lexer::LexTokenInternal.
   LangOpts.Digraphs = LexingStd >= FormatStyle::LS_Cpp11;
+  LangOpts.RawStringLiterals = LexingStd >= FormatStyle::LS_Cpp11;
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owenca wrote:

Can we set the default to 1 in `LangOpts.def`? That would take care of it.

https://github.com/llvm/llvm-project/pull/88265