[clang] [include-cleaner] Support multi-header symbols in mapping generator (PR #147720)

[kadir çetinkaya via cfe-commits]

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@@ -7,268 +7,6 @@
 
 // Symbols that can be provided by any of the headers, ordered by the header
 // preference.
-// cppreference mentions the <locale> header is an alternative for these symbols,
-// but they are not per the standard.
-SYMBOL(consume_header, std::, <codecvt>)
-SYMBOL(generate_header, std::, <codecvt>)
-SYMBOL(little_endian, std::, <codecvt>)
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kadircet wrote:

fwiw, these are reported as zombie-names per standard, https://eel.is/c++draft/zombie.names. moreover we aren't changing the preferred header. so I wouldn't pay too much attention here. these names availability depends on the language standard, which is a feature we're missing for other symbols as well.

https://github.com/llvm/llvm-project/pull/147720