Adding eosio::structure attribute

include/clang/AST/DeclCXX.h

@@ -730,10 +730,12 @@ class CXXRecordDecl : public RecordDecl {
   bool isEosioContract() const { return hasAttr<EosioContractAttr>(); }
   bool isEosioAction() const { return hasAttr<EosioActionAttr>(); }
   bool isEosioTable() const { return hasAttr<EosioTableAttr>(); }
+  bool isEosioStructure() const { return hasAttr<EosioStructureAttr>(); }
   bool isEosioIgnore() const { return hasAttr<EosioIgnoreAttr>(); }
   bool hasEosioRicardian() const { return hasAttr<EosioRicardianAttr>(); }
   EosioActionAttr* getEosioActionAttr() const { return getAttr<EosioActionAttr>(); }
   EosioTableAttr*  getEosioTableAttr() const { return getAttr<EosioTableAttr>(); }
+  EosioStructureAttr*  getEosioStructureAttr() const { return getAttr<EosioStructureAttr>(); }
   EosioContractAttr*  getEosioContractAttr() const { return getAttr<EosioContractAttr>(); }
   EosioRicardianAttr*  getEosioRicardianAttr() const { return getAttr<EosioRicardianAttr>(); }
 

include/clang/Basic/Attr.td

@@ -1104,6 +1104,14 @@ def EosioTable : InheritableAttr {
    let Documentation = [EosioTableDocs];
 }
 
+def EosioStructure : InheritableAttr {
+   let Spellings = [CXX11<"eosio", "structure">, GNU<"eosio_structure">];
+   let Args = [StringArgument<"name", 1>];
+   let Subjects = SubjectList<[CXXRecord]>;
+   let MeaningfulToClassTemplateDefinition = 1;
+   let Documentation = [EosioStructureDocs];
+}
+
 def CXX11NoReturn : InheritableAttr {
   let Spellings = [CXX11<"", "noreturn", 200809>];
   let Subjects = SubjectList<[Function], ErrorDiag>;

include/clang/Basic/AttrDocs.td

@@ -1043,6 +1043,13 @@ The ``eosio::table`` attribute marks a record as being an eosio table.
   }];
 }
 
+def EosioStructureDocs : Documentation {
+  let Category = DocCatFunction;
+  let Content = [{
+The ``eosio::structure`` attribute marks a struct as being an eosio structure.
+  }];
+}
+
 def NoSplitStackDocs : Documentation {
   let Category = DocCatFunction;
   let Content = [{
@@ -4237,4 +4244,4 @@ be accessed on both device side and host side. It has external linkage and is
 not initialized on device side. It has internal linkage and is initialized by
 the initializer on host side.
   }];
-}
+}

lib/Sema/SemaDeclAttr.cpp

@@ -489,6 +489,18 @@ static void handleEosioTableAttribute(Sema &S, Decl *D, const ParsedAttr &AL) {
                                 AL.getAttributeSpellingListIndex()));
 }
 
+static void handleEosioStructureAttribute(Sema &S, Decl *D, const ParsedAttr &AL) {
+  // Handle the cases where the attribute has a text message.
+  StringRef Str;
+  if (AL.isArgExpr(0) && AL.getArgAsExpr(0) &&
+      !S.checkStringLiteralArgumentAttr(AL, 0, Str))
+    return;
+
+  D->addAttr(::new (S.Context)
+                 EosioStructureAttr(AL.getRange(), S.Context, Str,
+                                AL.getAttributeSpellingListIndex()));
+}
+
 /// Applies the given attribute to the Decl without performing any
 /// additional semantic checking.
 template <typename AttrType>
@@ -6746,6 +6758,9 @@ static void ProcessDeclAttribute(Sema &S, Scope *scope, Decl *D,
   case ParsedAttr::AT_EosioTable:
     handleEosioTableAttribute(S, D, AL);
     break;
+  case ParsedAttr::AT_EosioStructure:
+    handleEosioStructureAttribute(S, D, AL);
+    break;
   case ParsedAttr::AT_EosioWasmABI:
     handleEosioABIAttribute(S, D, AL);
     break;