[clang] [clang] Introduce copy-on-write `CompilerInvocation` (PR #65412)

[Ben Langmuir via cfe-commits]

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@@ -94,47 +96,37 @@ class CompilerInvocationRefBase {
   /// Options controlling the static analyzer.
   AnalyzerOptionsRef AnalyzerOpts;
 
-  CompilerInvocationRefBase();
-  CompilerInvocationRefBase(const CompilerInvocationRefBase &X);
-  CompilerInvocationRefBase(CompilerInvocationRefBase &&X);
-  CompilerInvocationRefBase &operator=(CompilerInvocationRefBase X);
-  CompilerInvocationRefBase &operator=(CompilerInvocationRefBase &&X);
-  ~CompilerInvocationRefBase();
+  struct ShallowCopy {};
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benlangmuir wrote:

Maybe worth a doc comment for these types. I think it's clear what's going on in the constructors themselves, but if someone sees the type itself they might wonder.

https://github.com/llvm/llvm-project/pull/65412