Consume is_va_arg attr from IR

Author: lucic71

cpp2rust/converter/converter.cpp

@@ -4132,6 +4132,8 @@ std::string Converter::ConvertIRFragment(
           .is_index_base = ph->is_index_base,
       };
       result += ConvertPlaceholder(expr, arg, ph_ctx);
+    } else if (std::get_if<TranslationRule::VaArgsFragment>(&frag)) {
+      result += ConvertVariadicTail(expr, all_args);
     } else if (auto *mc =
                    std::get_if<std::unique_ptr<MethodCallFragment>>(&frag)) {
       result += ConvertMappedMethodCall(expr, **mc, args, num_args, ctx);
@@ -4141,6 +4143,25 @@ std::string Converter::ConvertIRFragment(
   return result;
 }
 
+std::string
+Converter::ConvertVariadicTail(clang::Expr *expr,
+                               const std::vector<clang::Expr *> &all_args) {
+  const auto *tgt_ir = Mapper::GetExprRule(GetCalleeOrExpr(expr));
+  unsigned fixed = tgt_ir ? tgt_ir->params.size() : 0;
+
+  Buffer buf(*this);
+  StrCat("&[");
+  for (unsigned i = fixed; i < all_args.size(); ++i) {
+    {
+      PushParen p(*this);
+      ConvertVariadicArg(all_args[i]);
+    }
+    StrCat(".into()", token::kComma);
+  }
+  StrCat("]");
+  return std::move(buf).str();
+}
+
 std::string Converter::AccessLValueObject(clang::MemberExpr *member) {
   auto *object = member->getBase();
   auto type = object->getType();

cpp2rust/converter/converter.h

@@ -563,6 +563,9 @@ class Converter : public clang::RecursiveASTVisitor<Converter> {
   std::string ConvertPlaceholder(clang::Expr *expr, clang::Expr *arg,
                                  const PlaceholderCtx &ph_ctx);
 
+  std::string ConvertVariadicTail(clang::Expr *expr,
+                                  const std::vector<clang::Expr *> &all_args);
+
   virtual std::string ConvertMappedMethodCall(
       clang::Expr *expr, const TranslationRule::MethodCallFragment &mc,
       clang::Expr **args, unsigned num_args, TempMaterializationCtx *ctx);

cpp2rust/converter/translation_rule.cpp

@@ -80,6 +80,8 @@ std::vector<BodyFragment> ParseBodyFragmentsJSON(const llvm::json::Array &arr) {
     } else if (auto *mc = frag_obj->getObject("method_call")) {
       result.push_back(std::make_unique<MethodCallFragment>(
           ParseMethodCallFragmentJSON(*mc)));
+    } else if (frag_obj->get("va_args")) {
+      result.push_back(VaArgsFragment{});
     }
   }
   return result;
@@ -222,6 +224,8 @@ void BodyFragmentDump(const BodyFragment &frag) {
     p->dump();
   } else if (auto *g = std::get_if<GenericFragment>(&frag)) {
     g->dump();
+  } else if (auto *v = std::get_if<VaArgsFragment>(&frag)) {
+    v->dump();
   } else if (auto *mc =
                  std::get_if<std::unique_ptr<MethodCallFragment>>(&frag)) {
     (*mc)->dump();
@@ -232,6 +236,8 @@ void BodyFragmentDump(const BodyFragment &frag) {
 
 void TextFragment::dump() const { log() << "  text: \"" << text << "\"\n"; }
 
+void VaArgsFragment::dump() const { log() << "  va_args\n"; }
+
 void PlaceholderFragment::dump() const {
   log() << "  placeholder: " << n;
   switch (access) {

cpp2rust/converter/translation_rule.h

@@ -39,11 +39,15 @@ struct GenericFragment {
   void dump() const;
 };
 
+struct VaArgsFragment {
+  void dump() const;
+};
+
 struct MethodCallFragment; // forward declaration
 
 using BodyFragment =
     std::variant<TextFragment, PlaceholderFragment, GenericFragment,
-                 std::unique_ptr<MethodCallFragment>>;
+                 VaArgsFragment, std::unique_ptr<MethodCallFragment>>;
 
 struct MethodCallFragment {
   std::vector<BodyFragment> receiver;