Add rust-type-resolution

2 files changed, 1089 insertions, 0 deletions

diff --git a/gcc/rust/analysis/rust-type-resolution.cc b/gcc/rust/analysis/rust-type-resolution.cc
new file mode 100644
index 0000000..f56a9eb
--- /dev/null
+++ b/gcc/rust/analysis/rust-type-resolution.cc
@@ -0,0 +1,863 @@
+#include "rust-type-resolution.h"
+#include "rust-diagnostics.h"
+
+#define ADD_BUILTIN_TYPE(_X, _S)                                               \
+  do                                                                           \
+    {                                                                          \
+      AST::PathIdentSegment seg (_X);                                          \
+      auto typePath = ::std::unique_ptr<AST::TypePathSegment> (                \
+	new AST::TypePathSegment (::std::move (seg), false,                    \
+				  Linemap::unknown_location ()));              \
+      ::std::vector< ::std::unique_ptr<AST::TypePathSegment> > segs;           \
+      segs.push_back (::std::move (typePath));                                 \
+      auto bType = new AST::TypePath (::std::move (segs),                      \
+				      Linemap::unknown_location (), false);    \
+      _S.Insert (_X, bType);                                                   \
+    }                                                                          \
+  while (0)
+
+namespace Rust {
+namespace Analysis {
+
+TypeResolution::TypeResolution (AST::Crate &crate, TopLevelScan &toplevel)
+  : Resolution (crate, toplevel)
+{
+  // push all builtin types - this is probably too basic for future needs
+  ADD_BUILTIN_TYPE ("u8", typeScope);
+  ADD_BUILTIN_TYPE ("u16", typeScope);
+  ADD_BUILTIN_TYPE ("u32", typeScope);
+  ADD_BUILTIN_TYPE ("u64", typeScope);
+
+  ADD_BUILTIN_TYPE ("i8", typeScope);
+  ADD_BUILTIN_TYPE ("i16", typeScope);
+  ADD_BUILTIN_TYPE ("i32", typeScope);
+  ADD_BUILTIN_TYPE ("i64", typeScope);
+
+  ADD_BUILTIN_TYPE ("f32", typeScope);
+  ADD_BUILTIN_TYPE ("f64", typeScope);
+
+  ADD_BUILTIN_TYPE ("char", typeScope);
+  ADD_BUILTIN_TYPE ("str", typeScope);
+  ADD_BUILTIN_TYPE ("bool", typeScope);
+}
+
+TypeResolution::~TypeResolution ()
+{
+  typeScope.Pop ();
+  scope.Pop ();
+}
+
+bool
+TypeResolution::Resolve (AST::Crate &crate, TopLevelScan &toplevel)
+{
+  TypeResolution resolver (crate, toplevel);
+  return resolver.go ();
+}
+
+bool
+TypeResolution::go ()
+{
+  for (auto &item : crate.items)
+    item->accept_vis (*this);
+
+  return true;
+}
+
+bool
+TypeResolution::typesAreCompatible (AST::Type *lhs, AST::Type *rhs,
+				    Location locus)
+{
+  lhs->accept_vis (*this);
+  rhs->accept_vis (*this);
+
+  auto rhsTypeStr = typeComparisonBuffer.back ();
+  typeComparisonBuffer.pop_back ();
+  auto lhsTypeStr = typeComparisonBuffer.back ();
+  typeComparisonBuffer.pop_back ();
+
+  // FIXME this needs to handle the cases of an i8 going into an i32 which is
+  // compatible
+  if (lhsTypeStr.compare (rhsTypeStr))
+    {
+      rust_error_at (locus, "E0308: expected: %s, found %s",
+		     lhsTypeStr.c_str (), rhsTypeStr.c_str ());
+      return false;
+    }
+
+  return true;
+}
+
+void
+TypeResolution::visit (AST::Token &tok)
+{}
+
+void
+TypeResolution::visit (AST::DelimTokenTree &delim_tok_tree)
+{}
+
+void
+TypeResolution::visit (AST::AttrInputMetaItemContainer &input)
+{}
+
+void
+TypeResolution::visit (AST::IdentifierExpr &ident_expr)
+{
+  AST::Type *type = NULL;
+  bool ok = scope.Lookup (ident_expr.ident, &type);
+  if (!ok)
+    {
+      rust_error_at (ident_expr.locus, "unknown identifier");
+      return;
+    }
+
+  typeBuffer.push_back (type);
+}
+
+void
+TypeResolution::visit (AST::Lifetime &lifetime)
+{}
+
+void
+TypeResolution::visit (AST::LifetimeParam &lifetime_param)
+{}
+
+void
+TypeResolution::visit (AST::MacroInvocationSemi &macro)
+{}
+
+// rust-path.h
+void
+TypeResolution::visit (AST::PathInExpression &path)
+{
+  printf ("PathInExpression: %s\n", path.as_string ().c_str ());
+}
+
+void
+TypeResolution::visit (AST::TypePathSegment &segment)
+{}
+void
+TypeResolution::visit (AST::TypePathSegmentGeneric &segment)
+{}
+
+void
+TypeResolution::visit (AST::TypePathSegmentFunction &segment)
+{}
+
+void
+TypeResolution::visit (AST::TypePath &path)
+{
+  // this may not be robust enough for type comparisons but lets try it for now
+  typeComparisonBuffer.push_back (path.as_string ());
+}
+
+void
+TypeResolution::visit (AST::QualifiedPathInExpression &path)
+{
+  typeComparisonBuffer.push_back (path.as_string ());
+}
+
+void
+TypeResolution::visit (AST::QualifiedPathInType &path)
+{
+  typeComparisonBuffer.push_back (path.as_string ());
+}
+
+// rust-expr.h
+void
+TypeResolution::visit (AST::LiteralExpr &expr)
+{
+  std::string type;
+  switch (expr.literal.get_lit_type ())
+    {
+    case AST::Literal::CHAR:
+      type = "char";
+      break;
+
+    case AST::Literal::STRING:
+    case AST::Literal::RAW_STRING:
+      type = "str";
+      break;
+
+    case AST::Literal::BOOL:
+      type = "bool";
+      break;
+
+    case AST::Literal::BYTE:
+      type = "u8";
+      break;
+
+      // FIXME these are not always going to be the case
+      // eg: suffix on the value can change the type
+    case AST::Literal::FLOAT:
+      type = "f32";
+      break;
+
+    case AST::Literal::INT:
+      type = "i32";
+      break;
+
+    case AST::Literal::BYTE_STRING:
+    case AST::Literal::RAW_BYTE_STRING:
+      // FIXME
+      break;
+    }
+
+  if (type.empty ())
+    {
+      rust_error_at (expr.locus, "unknown literal: %s",
+		     expr.literal.as_string ().c_str ());
+      return;
+    }
+
+  AST::Type *val = NULL;
+  bool ok = typeScope.Lookup (type, &val);
+  if (ok)
+    typeBuffer.push_back (val);
+  else
+    rust_error_at (expr.locus, "unknown literal type: %s", type.c_str ());
+}
+
+void
+TypeResolution::visit (AST::AttrInputLiteral &attr_input)
+{}
+
+void
+TypeResolution::visit (AST::MetaItemLitExpr &meta_item)
+{}
+
+void
+TypeResolution::visit (AST::MetaItemPathLit &meta_item)
+{}
+
+void
+TypeResolution::visit (AST::BorrowExpr &expr)
+{}
+void
+TypeResolution::visit (AST::DereferenceExpr &expr)
+{}
+void
+TypeResolution::visit (AST::ErrorPropagationExpr &expr)
+{}
+void
+TypeResolution::visit (AST::NegationExpr &expr)
+{}
+
+void
+TypeResolution::visit (AST::ArithmeticOrLogicalExpr &expr)
+{
+  size_t before;
+  before = typeBuffer.size ();
+  expr.visit_lhs (*this);
+  if (typeBuffer.size () <= before)
+    {
+      rust_error_at (expr.locus, "unable to determine lhs type");
+      return;
+    }
+
+  auto lhsType = typeBuffer.back ();
+  typeBuffer.pop_back ();
+
+  before = typeBuffer.size ();
+  expr.visit_rhs (*this);
+  if (typeBuffer.size () <= before)
+    {
+      rust_error_at (expr.locus, "unable to determine rhs type");
+      return;
+    }
+
+  auto rhsType = typeBuffer.back ();
+  // not poping because we will be checking they match and the
+  // scope will require knowledge of the type
+
+  // do the lhsType and the rhsType match
+  typesAreCompatible (lhsType, rhsType, expr.right_expr->get_locus_slow ());
+}
+
+void
+TypeResolution::visit (AST::ComparisonExpr &expr)
+{}
+
+void
+TypeResolution::visit (AST::LazyBooleanExpr &expr)
+{}
+
+void
+TypeResolution::visit (AST::TypeCastExpr &expr)
+{}
+
+void
+TypeResolution::visit (AST::AssignmentExpr &expr)
+{
+  size_t before;
+  before = typeBuffer.size ();
+  expr.visit_lhs (*this);
+  if (typeBuffer.size () <= before)
+    {
+      rust_error_at (expr.locus, "unable to determine lhs type");
+      return;
+    }
+
+  auto lhsType = typeBuffer.back ();
+  typeBuffer.pop_back ();
+
+  before = typeBuffer.size ();
+  expr.visit_rhs (*this);
+  if (typeBuffer.size () <= before)
+    {
+      rust_error_at (expr.locus, "unable to determine rhs type");
+      return;
+    }
+
+  auto rhsType = typeBuffer.back ();
+  // not poping because we will be checking they match and the
+  // scope will require knowledge of the type
+
+  // do the lhsType and the rhsType match
+  if (!typesAreCompatible (lhsType, rhsType,
+			   expr.right_expr->get_locus_slow ()))
+    return;
+
+  // is the lhs mutable?
+}
+
+void
+TypeResolution::visit (AST::CompoundAssignmentExpr &expr)
+{}
+
+void
+TypeResolution::visit (AST::GroupedExpr &expr)
+{}
+// void TypeResolution::visit(ArrayElems& elems) {}
+void
+TypeResolution::visit (AST::ArrayElemsValues &elems)
+{}
+void
+TypeResolution::visit (AST::ArrayElemsCopied &elems)
+{}
+void
+TypeResolution::visit (AST::ArrayExpr &expr)
+{}
+void
+TypeResolution::visit (AST::ArrayIndexExpr &expr)
+{}
+void
+TypeResolution::visit (AST::TupleExpr &expr)
+{}
+void
+TypeResolution::visit (AST::TupleIndexExpr &expr)
+{}
+void
+TypeResolution::visit (AST::StructExprStruct &expr)
+{}
+// void TypeResolution::visit(StructExprField& field) {}
+void
+TypeResolution::visit (AST::StructExprFieldIdentifier &field)
+{}
+void
+TypeResolution::visit (AST::StructExprFieldIdentifierValue &field)
+{}
+void
+TypeResolution::visit (AST::StructExprFieldIndexValue &field)
+{}
+void
+TypeResolution::visit (AST::StructExprStructFields &expr)
+{}
+void
+TypeResolution::visit (AST::StructExprStructBase &expr)
+{}
+void
+TypeResolution::visit (AST::StructExprTuple &expr)
+{}
+void
+TypeResolution::visit (AST::StructExprUnit &expr)
+{}
+// void TypeResolution::visit(EnumExprField& field) {}
+void
+TypeResolution::visit (AST::EnumExprFieldIdentifier &field)
+{}
+void
+TypeResolution::visit (AST::EnumExprFieldIdentifierValue &field)
+{}
+void
+TypeResolution::visit (AST::EnumExprFieldIndexValue &field)
+{}
+void
+TypeResolution::visit (AST::EnumExprStruct &expr)
+{}
+void
+TypeResolution::visit (AST::EnumExprTuple &expr)
+{}
+void
+TypeResolution::visit (AST::EnumExprFieldless &expr)
+{}
+
+void
+TypeResolution::visit (AST::CallExpr &expr)
+{
+  printf ("CallExpr: %s\n", expr.as_string ().c_str ());
+}
+
+void
+TypeResolution::visit (AST::MethodCallExpr &expr)
+{}
+void
+TypeResolution::visit (AST::FieldAccessExpr &expr)
+{}
+void
+TypeResolution::visit (AST::ClosureExprInner &expr)
+{}
+void
+TypeResolution::visit (AST::BlockExpr &expr)
+{}
+void
+TypeResolution::visit (AST::ClosureExprInnerTyped &expr)
+{}
+void
+TypeResolution::visit (AST::ContinueExpr &expr)
+{}
+void
+TypeResolution::visit (AST::BreakExpr &expr)
+{}
+void
+TypeResolution::visit (AST::RangeFromToExpr &expr)
+{}
+void
+TypeResolution::visit (AST::RangeFromExpr &expr)
+{}
+void
+TypeResolution::visit (AST::RangeToExpr &expr)
+{}
+void
+TypeResolution::visit (AST::RangeFullExpr &expr)
+{}
+void
+TypeResolution::visit (AST::RangeFromToInclExpr &expr)
+{}
+void
+TypeResolution::visit (AST::RangeToInclExpr &expr)
+{}
+void
+TypeResolution::visit (AST::ReturnExpr &expr)
+{}
+void
+TypeResolution::visit (AST::UnsafeBlockExpr &expr)
+{}
+void
+TypeResolution::visit (AST::LoopExpr &expr)
+{}
+void
+TypeResolution::visit (AST::WhileLoopExpr &expr)
+{}
+void
+TypeResolution::visit (AST::WhileLetLoopExpr &expr)
+{}
+void
+TypeResolution::visit (AST::ForLoopExpr &expr)
+{}
+void
+TypeResolution::visit (AST::IfExpr &expr)
+{}
+void
+TypeResolution::visit (AST::IfExprConseqElse &expr)
+{}
+void
+TypeResolution::visit (AST::IfExprConseqIf &expr)
+{}
+void
+TypeResolution::visit (AST::IfExprConseqIfLet &expr)
+{}
+void
+TypeResolution::visit (AST::IfLetExpr &expr)
+{}
+void
+TypeResolution::visit (AST::IfLetExprConseqElse &expr)
+{}
+void
+TypeResolution::visit (AST::IfLetExprConseqIf &expr)
+{}
+void
+TypeResolution::visit (AST::IfLetExprConseqIfLet &expr)
+{}
+// void TypeResolution::visit(MatchCase& match_case) {}
+void
+TypeResolution::visit (AST::MatchCaseBlockExpr &match_case)
+{}
+void
+TypeResolution::visit (AST::MatchCaseExpr &match_case)
+{}
+void
+TypeResolution::visit (AST::MatchExpr &expr)
+{}
+void
+TypeResolution::visit (AST::AwaitExpr &expr)
+{}
+void
+TypeResolution::visit (AST::AsyncBlockExpr &expr)
+{}
+
+// rust-item.h
+void
+TypeResolution::visit (AST::TypeParam &param)
+{}
+// void TypeResolution::visit(WhereClauseItem& item) {}
+void
+TypeResolution::visit (AST::LifetimeWhereClauseItem &item)
+{}
+void
+TypeResolution::visit (AST::TypeBoundWhereClauseItem &item)
+{}
+void
+TypeResolution::visit (AST::Method &method)
+{}
+void
+TypeResolution::visit (AST::ModuleBodied &module)
+{}
+void
+TypeResolution::visit (AST::ModuleNoBody &module)
+{}
+void
+TypeResolution::visit (AST::ExternCrate &crate)
+{}
+// void TypeResolution::visit(UseTree& use_tree) {}
+void
+TypeResolution::visit (AST::UseTreeGlob &use_tree)
+{}
+void
+TypeResolution::visit (AST::UseTreeList &use_tree)
+{}
+void
+TypeResolution::visit (AST::UseTreeRebind &use_tree)
+{}
+void
+TypeResolution::visit (AST::UseDeclaration &use_decl)
+{}
+
+void
+TypeResolution::visit (AST::Function &function)
+{
+  // always emit the function with return type in the event of nil return type
+  // its  a marker for a void function
+  scope.Insert (function.function_name, function.return_type.get ());
+
+  scope.Push ();
+  for (auto &param : function.function_params)
+    {
+      auto before = letPatternBuffer.size ();
+      param.param_name->accept_vis (*this);
+      if (letPatternBuffer.size () <= before)
+	{
+	  rust_error_at (param.locus, "failed to analyse parameter name");
+	  return;
+	}
+
+      auto paramName = letPatternBuffer.back ();
+      letPatternBuffer.pop_back ();
+      scope.Insert (paramName.variable_ident, param.type.get ());
+    }
+
+  // walk the expression body
+  for (auto &stmt : function.function_body->statements)
+    {
+      stmt->accept_vis (*this);
+    }
+
+  scope.Pop ();
+}
+
+void
+TypeResolution::visit (AST::TypeAlias &type_alias)
+{}
+void
+TypeResolution::visit (AST::StructStruct &struct_item)
+{}
+void
+TypeResolution::visit (AST::TupleStruct &tuple_struct)
+{}
+void
+TypeResolution::visit (AST::EnumItem &item)
+{}
+void
+TypeResolution::visit (AST::EnumItemTuple &item)
+{}
+void
+TypeResolution::visit (AST::EnumItemStruct &item)
+{}
+void
+TypeResolution::visit (AST::EnumItemDiscriminant &item)
+{}
+void
+TypeResolution::visit (AST::Enum &enum_item)
+{}
+void
+TypeResolution::visit (AST::Union &union_item)
+{}
+
+void
+TypeResolution::visit (AST::ConstantItem &const_item)
+{
+  printf ("ConstantItem: %s\n", const_item.as_string ().c_str ());
+}
+
+void
+TypeResolution::visit (AST::StaticItem &static_item)
+{}
+void
+TypeResolution::visit (AST::TraitItemFunc &item)
+{}
+void
+TypeResolution::visit (AST::TraitItemMethod &item)
+{}
+void
+TypeResolution::visit (AST::TraitItemConst &item)
+{}
+void
+TypeResolution::visit (AST::TraitItemType &item)
+{}
+void
+TypeResolution::visit (AST::Trait &trait)
+{}
+void
+TypeResolution::visit (AST::InherentImpl &impl)
+{}
+void
+TypeResolution::visit (AST::TraitImpl &impl)
+{}
+// void TypeResolution::visit(ExternalItem& item) {}
+void
+TypeResolution::visit (AST::ExternalStaticItem &item)
+{}
+void
+TypeResolution::visit (AST::ExternalFunctionItem &item)
+{}
+void
+TypeResolution::visit (AST::ExternBlock &block)
+{}
+
+// rust-macro.h
+void
+TypeResolution::visit (AST::MacroMatchFragment &match)
+{}
+void
+TypeResolution::visit (AST::MacroMatchRepetition &match)
+{}
+void
+TypeResolution::visit (AST::MacroMatcher &matcher)
+{}
+void
+TypeResolution::visit (AST::MacroRulesDefinition &rules_def)
+{}
+void
+TypeResolution::visit (AST::MacroInvocation &macro_invoc)
+{}
+void
+TypeResolution::visit (AST::MetaItemPath &meta_item)
+{}
+void
+TypeResolution::visit (AST::MetaItemSeq &meta_item)
+{}
+void
+TypeResolution::visit (AST::MetaWord &meta_item)
+{}
+void
+TypeResolution::visit (AST::MetaNameValueStr &meta_item)
+{}
+void
+TypeResolution::visit (AST::MetaListPaths &meta_item)
+{}
+void
+TypeResolution::visit (AST::MetaListNameValueStr &meta_item)
+{}
+
+// rust-pattern.h
+void
+TypeResolution::visit (AST::LiteralPattern &pattern)
+{
+  printf ("LiteralPattern: %s\n", pattern.as_string ().c_str ());
+}
+
+void
+TypeResolution::visit (AST::IdentifierPattern &pattern)
+{
+  letPatternBuffer.push_back (pattern);
+}
+
+void
+TypeResolution::visit (AST::WildcardPattern &pattern)
+{}
+// void TypeResolution::visit(RangePatternBound& bound) {}
+void
+TypeResolution::visit (AST::RangePatternBoundLiteral &bound)
+{}
+void
+TypeResolution::visit (AST::RangePatternBoundPath &bound)
+{}
+void
+TypeResolution::visit (AST::RangePatternBoundQualPath &bound)
+{}
+void
+TypeResolution::visit (AST::RangePattern &pattern)
+{}
+void
+TypeResolution::visit (AST::ReferencePattern &pattern)
+{}
+// void TypeResolution::visit(StructPatternField& field) {}
+void
+TypeResolution::visit (AST::StructPatternFieldTuplePat &field)
+{}
+void
+TypeResolution::visit (AST::StructPatternFieldIdentPat &field)
+{}
+void
+TypeResolution::visit (AST::StructPatternFieldIdent &field)
+{}
+void
+TypeResolution::visit (AST::StructPattern &pattern)
+{}
+// void TypeResolution::visit(TupleStructItems& tuple_items) {}
+void
+TypeResolution::visit (AST::TupleStructItemsNoRange &tuple_items)
+{}
+void
+TypeResolution::visit (AST::TupleStructItemsRange &tuple_items)
+{}
+void
+TypeResolution::visit (AST::TupleStructPattern &pattern)
+{}
+// void TypeResolution::visit(TuplePatternItems& tuple_items) {}
+void
+TypeResolution::visit (AST::TuplePatternItemsMultiple &tuple_items)
+{}
+void
+TypeResolution::visit (AST::TuplePatternItemsRanged &tuple_items)
+{}
+void
+TypeResolution::visit (AST::TuplePattern &pattern)
+{}
+void
+TypeResolution::visit (AST::GroupedPattern &pattern)
+{}
+void
+TypeResolution::visit (AST::SlicePattern &pattern)
+{}
+
+// rust-stmt.h
+void
+TypeResolution::visit (AST::EmptyStmt &stmt)
+{}
+
+void
+TypeResolution::visit (AST::LetStmt &stmt)
+{
+  if (!stmt.has_init_expr () && !stmt.has_type ())
+    {
+      rust_error_at (stmt.locus,
+		     "E0282: type annotations or init expression needed");
+      return;
+    }
+
+  AST::Type *inferedType = NULL;
+  if (stmt.has_init_expr ())
+    {
+      stmt.init_expr->accept_vis (*this);
+
+      if (typeBuffer.empty ())
+	{
+	  rust_error_at (
+	    stmt.init_expr->get_locus_slow (),
+	    "unable to determine type for declaration from init expr");
+	  return;
+	}
+
+      inferedType = typeBuffer.back ();
+      typeBuffer.pop_back ();
+    }
+
+  if (stmt.has_type () && stmt.has_init_expr ())
+    {
+      if (!typesAreCompatible (stmt.type.get (), inferedType,
+			       stmt.init_expr->get_locus_slow ()))
+	{
+	  return;
+	}
+    }
+  else if (stmt.has_type () && !stmt.has_init_expr ())
+    {
+      inferedType = stmt.type.get ();
+    }
+
+  // TODO check we know what the type is in the scope requires the builtins to
+  // be defined at the constructor
+
+  // ensure the decl has the type set for compilation later on
+  if (!stmt.has_type ())
+    {
+      stmt.inferedType = inferedType;
+    }
+
+  // get all the names part of this declaration and add the types to the scope
+  stmt.variables_pattern->accept_vis (*this);
+  for (auto it = letPatternBuffer.begin (); it != letPatternBuffer.end (); it++)
+    {
+      scope.Insert (it->variable_ident, inferedType);
+    }
+  letPatternBuffer.clear ();
+}
+
+void
+TypeResolution::visit (AST::ExprStmtWithoutBlock &stmt)
+{
+  stmt.expr->accept_vis (*this);
+}
+
+void
+TypeResolution::visit (AST::ExprStmtWithBlock &stmt)
+{}
+
+// rust-type.h
+void
+TypeResolution::visit (AST::TraitBound &bound)
+{}
+
+void
+TypeResolution::visit (AST::ImplTraitType &type)
+{}
+
+void
+TypeResolution::visit (AST::TraitObjectType &type)
+{}
+void
+TypeResolution::visit (AST::ParenthesisedType &type)
+{}
+void
+TypeResolution::visit (AST::ImplTraitTypeOneBound &type)
+{}
+void
+TypeResolution::visit (AST::TraitObjectTypeOneBound &type)
+{}
+void
+TypeResolution::visit (AST::TupleType &type)
+{}
+void
+TypeResolution::visit (AST::NeverType &type)
+{}
+void
+TypeResolution::visit (AST::RawPointerType &type)
+{}
+void
+TypeResolution::visit (AST::ReferenceType &type)
+{}
+void
+TypeResolution::visit (AST::ArrayType &type)
+{}
+void
+TypeResolution::visit (AST::SliceType &type)
+{}
+void
+TypeResolution::visit (AST::InferredType &type)
+{}
+void
+TypeResolution::visit (AST::BareFunctionType &type)
+{}
+
+} // namespace Analysis
+} // namespace Rust
diff --git a/gcc/rust/analysis/rust-type-resolution.h b/gcc/rust/analysis/rust-type-resolution.h
new file mode 100644
index 0000000..5f8120c
--- /dev/null
+++ b/gcc/rust/analysis/rust-type-resolution.h
@@ -0,0 +1,226 @@
+#pragma once
+
+#include "rust-resolution.h"
+
+namespace Rust {
+namespace Analysis {
+
+class TypeResolution : public Resolution
+{
+public:
+  ~TypeResolution ();
+  static bool Resolve (AST::Crate &crate, TopLevelScan &toplevel);
+
+  // visitor impl
+  // rust-ast.h
+  //  void visit(AttrInput& attr_input);
+  //  void visit(TokenTree& token_tree);
+  //  void visit(MacroMatch& macro_match);
+  void visit (AST::Token &tok) override;
+  void visit (AST::DelimTokenTree &delim_tok_tree) override;
+  void visit (AST::AttrInputMetaItemContainer &input) override;
+  //  void visit(MetaItem& meta_item) override;
+  //  void vsit(Stmt& stmt) override;
+  //  void visit(Expr& expr) override;
+  void visit (AST::IdentifierExpr &ident_expr) override;
+  //  void visit(Pattern& pattern) override;
+  //  void visit(Type& type) override;
+  //  void visit(TypeParamBound& type_param_bound) override;
+  void visit (AST::Lifetime &lifetime) override;
+  //  void visit(GenericParam& generic_param) override;
+  void visit (AST::LifetimeParam &lifetime_param) override;
+  //  void visit(TraitItem& trait_item) override;
+  //  void visit(InherentImplItem& inherent_impl_item) override;
+  //  void visit(TraitImplItem& trait_impl_item) override;
+  void visit (AST::MacroInvocationSemi &macro) override;
+
+  // rust-path.h
+  void visit (AST::PathInExpression &path) override;
+  void visit (AST::TypePathSegment &segment) override;
+  void visit (AST::TypePathSegmentGeneric &segment) override;
+  void visit (AST::TypePathSegmentFunction &segment) override;
+  void visit (AST::TypePath &path) override;
+  void visit (AST::QualifiedPathInExpression &path) override;
+  void visit (AST::QualifiedPathInType &path) override;
+
+  // rust-expr.h
+  void visit (AST::LiteralExpr &expr) override;
+  void visit (AST::AttrInputLiteral &attr_input) override;
+  void visit (AST::MetaItemLitExpr &meta_item) override;
+  void visit (AST::MetaItemPathLit &meta_item) override;
+  void visit (AST::BorrowExpr &expr) override;
+  void visit (AST::DereferenceExpr &expr) override;
+  void visit (AST::ErrorPropagationExpr &expr) override;
+  void visit (AST::NegationExpr &expr) override;
+  void visit (AST::ArithmeticOrLogicalExpr &expr) override;
+  void visit (AST::ComparisonExpr &expr) override;
+  void visit (AST::LazyBooleanExpr &expr) override;
+  void visit (AST::TypeCastExpr &expr) override;
+  void visit (AST::AssignmentExpr &expr) override;
+  void visit (AST::CompoundAssignmentExpr &expr) override;
+  void visit (AST::GroupedExpr &expr) override;
+  //  void visit(ArrayElems& elems) override;
+  void visit (AST::ArrayElemsValues &elems) override;
+  void visit (AST::ArrayElemsCopied &elems) override;
+  void visit (AST::ArrayExpr &expr) override;
+  void visit (AST::ArrayIndexExpr &expr) override;
+  void visit (AST::TupleExpr &expr) override;
+  void visit (AST::TupleIndexExpr &expr) override;
+  void visit (AST::StructExprStruct &expr) override;
+  //  void visit(StructExprField& field) override;
+  void visit (AST::StructExprFieldIdentifier &field) override;
+  void visit (AST::StructExprFieldIdentifierValue &field) override;
+  void visit (AST::StructExprFieldIndexValue &field) override;
+  void visit (AST::StructExprStructFields &expr) override;
+  void visit (AST::StructExprStructBase &expr) override;
+  void visit (AST::StructExprTuple &expr) override;
+  void visit (AST::StructExprUnit &expr) override;
+  //  void visit(EnumExprField& field) override;
+  void visit (AST::EnumExprFieldIdentifier &field) override;
+  void visit (AST::EnumExprFieldIdentifierValue &field) override;
+  void visit (AST::EnumExprFieldIndexValue &field) override;
+  void visit (AST::EnumExprStruct &expr) override;
+  void visit (AST::EnumExprTuple &expr) override;
+  void visit (AST::EnumExprFieldless &expr) override;
+  void visit (AST::CallExpr &expr) override;
+  void visit (AST::MethodCallExpr &expr) override;
+  void visit (AST::FieldAccessExpr &expr) override;
+  void visit (AST::ClosureExprInner &expr) override;
+  void visit (AST::BlockExpr &expr) override;
+  void visit (AST::ClosureExprInnerTyped &expr) override;
+  void visit (AST::ContinueExpr &expr) override;
+  void visit (AST::BreakExpr &expr) override;
+  void visit (AST::RangeFromToExpr &expr) override;
+  void visit (AST::RangeFromExpr &expr) override;
+  void visit (AST::RangeToExpr &expr) override;
+  void visit (AST::RangeFullExpr &expr) override;
+  void visit (AST::RangeFromToInclExpr &expr) override;
+  void visit (AST::RangeToInclExpr &expr) override;
+  void visit (AST::ReturnExpr &expr) override;
+  void visit (AST::UnsafeBlockExpr &expr) override;
+  void visit (AST::LoopExpr &expr) override;
+  void visit (AST::WhileLoopExpr &expr) override;
+  void visit (AST::WhileLetLoopExpr &expr) override;
+  void visit (AST::ForLoopExpr &expr) override;
+  void visit (AST::IfExpr &expr) override;
+  void visit (AST::IfExprConseqElse &expr) override;
+  void visit (AST::IfExprConseqIf &expr) override;
+  void visit (AST::IfExprConseqIfLet &expr) override;
+  void visit (AST::IfLetExpr &expr) override;
+  void visit (AST::IfLetExprConseqElse &expr) override;
+  void visit (AST::IfLetExprConseqIf &expr) override;
+  void visit (AST::IfLetExprConseqIfLet &expr) override;
+  //  void visit(MatchCase& match_case) override;
+  void visit (AST::MatchCaseBlockExpr &match_case) override;
+  void visit (AST::MatchCaseExpr &match_case) override;
+  void visit (AST::MatchExpr &expr) override;
+  void visit (AST::AwaitExpr &expr) override;
+  void visit (AST::AsyncBlockExpr &expr) override;
+
+  // rust-item.h
+  void visit (AST::TypeParam &param) override;
+  //  void visit(WhereClauseItem& item) override;
+  void visit (AST::LifetimeWhereClauseItem &item) override;
+  void visit (AST::TypeBoundWhereClauseItem &item) override;
+  void visit (AST::Method &method) override;
+  void visit (AST::ModuleBodied &module) override;
+  void visit (AST::ModuleNoBody &module) override;
+  void visit (AST::ExternCrate &crate) override;
+  //  void visit(UseTree& use_tree) override;
+  void visit (AST::UseTreeGlob &use_tree) override;
+  void visit (AST::UseTreeList &use_tree) override;
+  void visit (AST::UseTreeRebind &use_tree) override;
+  void visit (AST::UseDeclaration &use_decl) override;
+  void visit (AST::Function &function) override;
+  void visit (AST::TypeAlias &type_alias) override;
+  void visit (AST::StructStruct &struct_item) override;
+  void visit (AST::TupleStruct &tuple_struct) override;
+  void visit (AST::EnumItem &item) override;
+  void visit (AST::EnumItemTuple &item) override;
+  void visit (AST::EnumItemStruct &item) override;
+  void visit (AST::EnumItemDiscriminant &item) override;
+  void visit (AST::Enum &enum_item) override;
+  void visit (AST::Union &union_item) override;
+  void visit (AST::ConstantItem &const_item) override;
+  void visit (AST::StaticItem &static_item) override;
+  void visit (AST::TraitItemFunc &item) override;
+  void visit (AST::TraitItemMethod &item) override;
+  void visit (AST::TraitItemConst &item) override;
+  void visit (AST::TraitItemType &item) override;
+  void visit (AST::Trait &trait) override;
+  void visit (AST::InherentImpl &impl) override;
+  void visit (AST::TraitImpl &impl) override;
+  //  void visit(ExternalItem& item) override;
+  void visit (AST::ExternalStaticItem &item) override;
+  void visit (AST::ExternalFunctionItem &item) override;
+  void visit (AST::ExternBlock &block) override;
+
+  // rust-macro.h
+  void visit (AST::MacroMatchFragment &match) override;
+  void visit (AST::MacroMatchRepetition &match) override;
+  void visit (AST::MacroMatcher &matcher) override;
+  void visit (AST::MacroRulesDefinition &rules_def) override;
+  void visit (AST::MacroInvocation &macro_invoc) override;
+  void visit (AST::MetaItemPath &meta_item) override;
+  void visit (AST::MetaItemSeq &meta_item) override;
+  void visit (AST::MetaWord &meta_item) override;
+  void visit (AST::MetaNameValueStr &meta_item) override;
+  void visit (AST::MetaListPaths &meta_item) override;
+  void visit (AST::MetaListNameValueStr &meta_item) override;
+
+  // rust-pattern.h
+  void visit (AST::LiteralPattern &pattern) override;
+  void visit (AST::IdentifierPattern &pattern) override;
+  void visit (AST::WildcardPattern &pattern) override;
+  //  void visit(RangePatternBound& bound) override;
+  void visit (AST::RangePatternBoundLiteral &bound) override;
+  void visit (AST::RangePatternBoundPath &bound) override;
+  void visit (AST::RangePatternBoundQualPath &bound) override;
+  void visit (AST::RangePattern &pattern) override;
+  void visit (AST::ReferencePattern &pattern) override;
+  //  void visit(StructPatternField& field) override;
+  void visit (AST::StructPatternFieldTuplePat &field) override;
+  void visit (AST::StructPatternFieldIdentPat &field) override;
+  void visit (AST::StructPatternFieldIdent &field) override;
+  void visit (AST::StructPattern &pattern) override;
+  //  void visit(TupleStructItems& tuple_items) override;
+  void visit (AST::TupleStructItemsNoRange &tuple_items) override;
+  void visit (AST::TupleStructItemsRange &tuple_items) override;
+  void visit (AST::TupleStructPattern &pattern) override;
+  //  void visit(TuplePatternItems& tuple_items) override;
+  void visit (AST::TuplePatternItemsMultiple &tuple_items) override;
+  void visit (AST::TuplePatternItemsRanged &tuple_items) override;
+  void visit (AST::TuplePattern &pattern) override;
+  void visit (AST::GroupedPattern &pattern) override;
+  void visit (AST::SlicePattern &pattern) override;
+
+  // rust-stmt.h
+  void visit (AST::EmptyStmt &stmt) override;
+  void visit (AST::LetStmt &stmt) override;
+  void visit (AST::ExprStmtWithoutBlock &stmt) override;
+  void visit (AST::ExprStmtWithBlock &stmt) override;
+
+  // rust-type.h
+  void visit (AST::TraitBound &bound) override;
+  void visit (AST::ImplTraitType &type) override;
+  void visit (AST::TraitObjectType &type) override;
+  void visit (AST::ParenthesisedType &type) override;
+  void visit (AST::ImplTraitTypeOneBound &type) override;
+  void visit (AST::TraitObjectTypeOneBound &type) override;
+  void visit (AST::TupleType &type) override;
+  void visit (AST::NeverType &type) override;
+  void visit (AST::RawPointerType &type) override;
+  void visit (AST::ReferenceType &type) override;
+  void visit (AST::ArrayType &type) override;
+  void visit (AST::SliceType &type) override;
+  void visit (AST::InferredType &type) override;
+  void visit (AST::BareFunctionType &type) override;
+
+private:
+  TypeResolution (AST::Crate &crate, TopLevelScan &toplevel);
+  bool go () override;
+  bool typesAreCompatible (AST::Type *lhs, AST::Type *rhs, Location locus);
+};
+
+} // namespace Analysis
+} // namespace Rust