[llvm] [Support] Add clang tooling generated explicit visibility macros (PR #113097)

[Saleem Abdulrasool via llvm-commits]

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@@ -103,12 +103,12 @@ namespace detail {
 template <typename Period> struct unit { static const char value[]; };
 template <typename Period> const char unit<Period>::value[] = "";
 
-template <> struct unit<std::ratio<3600>> { static const char value[]; };
-template <> struct unit<std::ratio<60>> { static const char value[]; };
-template <> struct unit<std::ratio<1>> { static const char value[]; };
-template <> struct unit<std::milli> { static const char value[]; };
-template <> struct unit<std::micro> { static const char value[]; };
-template <> struct unit<std::nano> { static const char value[]; };
+template <> struct LLVM_ABI unit<std::ratio<3600>> { static const char value[]; };
+template <> struct LLVM_ABI unit<std::ratio<60>> { static const char value[]; };
+template <> struct LLVM_ABI unit<std::ratio<1>> { static const char value[]; };
+template <> struct LLVM_ABI unit<std::milli> { static const char value[]; };
+template <> struct LLVM_ABI unit<std::micro> { static const char value[]; };
+template <> struct LLVM_ABI unit<std::nano> { static const char value[]; };
 } // namespace detail
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compnerd wrote:

Should these be/are they `extern template`'ed?

https://github.com/llvm/llvm-project/pull/113097