[clang] [llvm] Enable fexec-charset option (PR #138895)

[Sergei Barannikov via cfe-commits]

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@@ -507,6 +507,9 @@ class Triple {
   /// For example, "fooos1.2.3" would return "1.2.3".
   LLVM_ABI StringRef getEnvironmentVersionString() const;
 
+  /// getDefaultNarrowTextEncoding - Get the default encoding of the triple.
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s-barannikov wrote:

Quote from the coding standard:
> Don’t duplicate the function or class name at the beginning of the comment

Also, the comment could be more verbose, "default encoding of the triple" is confusing without a context.

https://github.com/llvm/llvm-project/pull/138895