[Lldb-commits] [clang] [lldb] [lldb] Re-use clang's keyword enable/disable mechanism in CPlusPlusNameParser.cpp (PR #164284)

[Daniel Sanders via lldb-commits]

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@@ -46,6 +46,59 @@ class LangOptions;
 class MultiKeywordSelector;
 class SourceLocation;
 
+// This is an inline namespace to allow both clang and lldb to use them without
+// namespace prefixes (via `using namespace` in lldb's case).
+inline namespace TokenKeyEnumerators {
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dsandersllvm wrote:

I don't mind splitting it but that PR won't make sense without the context of this PR

The reason we need the `inline namespace` is because of this code:
```
#define KEYWORD(NAME, FLAGS)                                                   \
  AddResult = getKeywordStatus(LangOpts, FLAGS);                               \
  ...
#include "clang/Basic/TokenKinds.def"
```
I can't reference `FLAGS` as `clang::FLAGS` because some of the `KEYWORD()` declaration's in TokenKinds.def are the `|` of multiple values such as `BOOLSUPPORT|KEYC23` and I'd need the namespace to appear on each identifier. `enum class` is ruled out for the same reason, and `enum class` combined with `using enum ...` requires C++20 and therefore can't be used.

`inline namespace` allows lldb to import them with `using namespace ...` for use as bare names without changing how clang uses them

https://github.com/llvm/llvm-project/pull/164284