[clang] [Clang] Implement the core language parts of P2786 - Trivial relocation (PR #127636)

[Erich Keane via cfe-commits]

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@@ -3808,13 +3866,39 @@ void Parser::ParseCXXMemberSpecification(SourceLocation RecordLoc,
   SourceLocation AbstractLoc;
   bool IsFinalSpelledSealed = false;
   bool IsAbstract = false;
+  TriviallyRelocatableSpecifier TriviallyRelocatable;
+  ReplaceableSpecifier Replacable;
 
   // Parse the optional 'final' keyword.
   if (getLangOpts().CPlusPlus && Tok.is(tok::identifier)) {
     while (true) {
       VirtSpecifiers::Specifier Specifier = isCXX11VirtSpecifier(Tok);
-      if (Specifier == VirtSpecifiers::VS_None)
-        break;
+      if (Specifier == VirtSpecifiers::VS_None) {
+        if (isCXX2CTriviallyRelocatableKeyword(Tok)) {
+          if (TriviallyRelocatable.isSet()) {
+            auto Skipped = Tok;
+            ConsumeToken();
+            Diag(Skipped, diag::err_duplicate_class_relocation_specifier)
+                << 0 << TriviallyRelocatable.getLocation();
+          } else {
+            ParseOptionalCXX2CTriviallyRelocatableSpecifier(
+                TriviallyRelocatable);
+          }
+          continue;
+        } else if (isCXX2CReplaceableKeyword(Tok)) {
+          if (Replacable.isSet()) {
+            auto Skipped = Tok;
+            ConsumeToken();
+            Diag(Skipped, diag::err_duplicate_class_relocation_specifier)
+                << 1 << Replacable.getLocation();
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erichkeane wrote:

here too.

https://github.com/llvm/llvm-project/pull/127636