[clang-tools-extra] [clang-doc] mangle template specialization file names (PR #144617)

[Paul Kirth via cfe-commits]

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@@ -209,6 +209,9 @@ struct TemplateSpecializationInfo {
 
   // Template parameters applying to the specialized record/function.
   std::vector<TemplateParamInfo> Params;
+
+  // Used to distinguish class specialization file names.
+  std::optional<SmallString<16>> MangledName;
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ilovepi wrote:

can you just always use a mangled name for everything? for C mangling would just be the name, but for anything in C++, it'd get you a unique name. Seems reasonable to do unconditionally. WDYT?

https://github.com/llvm/llvm-project/pull/144617