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

[via cfe-commits]

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@@ -130,6 +130,12 @@ struct LangStandard {
   /// hasDigraphs - Language supports digraphs.
   bool hasDigraphs() const { return Flags & Digraphs; }
 
+  /// hasRawStringLiterals - Language supports R"()" raw string literals.
+  bool hasRawStringLiterals() const {
+    // GCC supports raw string literals in C, but not in C++ before C++11.
+    return isCPlusPlus11() || (!isCPlusPlus() && isGNUMode());
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Sirraide wrote:

I’ll file a GCC bug report about it. In the meantime, should we be conservative and disallow them in gnu89 mode?

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