gccrs: make distinction between error and empty for substution args

When handling generics of only lifetimes we have an empty
SubstitutionArgumentMappings which was being detected as an error but this
is not the case as we don't currently handle const generics or generic
lifetimes so this makes the distinction between an error occurred or its
simply empty because it was all only lifetime arguments and we don't care
about it.

Addresses #2043 #2039

gcc/rust/ChangeLog:

	* typecheck/rust-tyty-bounds.cc (TypeBoundPredicate::TypeBoundPredicate): this is an empty
	(TypeBoundPredicate::operator=): likewise
	* typecheck/rust-tyty-subst.cc (SubstitutionArgumentMappings::empty): new interface
	(SubstitutionArgumentMappings::is_error): this marks it as an error
	* typecheck/rust-tyty-subst.h: update prototypes

Signed-off-by: Philip Herron <herron.philip@googlemail.com>

diff --git a/gcc/rust/typecheck/rust-tyty-bounds.cc b/gcc/rust/typecheck/rust-tyty-bounds.cc
index 6c36303baca578c688ee970f3b95cc970aa40ce0..6977bee2f3ff8c01539acf1379f5c17e4186ebb1 100644 (file)
--- a/gcc/rust/typecheck/rust-tyty-bounds.cc
+++ b/gcc/rust/typecheck/rust-tyty-bounds.cc
@@ -271,7 +271,7 @@ namespace TyTy {
 
 TypeBoundPredicate::TypeBoundPredicate (
   const Resolver::TraitReference &trait_reference, Location locus)
-  : SubstitutionRef ({}, SubstitutionArgumentMappings::error ()),
+  : SubstitutionRef ({}, SubstitutionArgumentMappings::empty ()),
     reference (trait_reference.get_mappings ().get_defid ()), locus (locus),
     error_flag (false)
 {
@@ -286,7 +286,7 @@ TypeBoundPredicate::TypeBoundPredicate (
 
 TypeBoundPredicate::TypeBoundPredicate (
   DefId reference, std::vector<SubstitutionParamMapping> subst, Location locus)
-  : SubstitutionRef ({}, SubstitutionArgumentMappings::error ()),
+  : SubstitutionRef ({}, SubstitutionArgumentMappings::empty ()),
     reference (reference), locus (locus), error_flag (false)
 {
   substitutions.clear ();
@@ -299,7 +299,7 @@ TypeBoundPredicate::TypeBoundPredicate (
 }
 
 TypeBoundPredicate::TypeBoundPredicate (const TypeBoundPredicate &other)
-  : SubstitutionRef ({}, SubstitutionArgumentMappings::error ()),
+  : SubstitutionRef ({}, SubstitutionArgumentMappings::empty ()),
     reference (other.reference), locus (other.locus),
     error_flag (other.error_flag)
 {
@@ -337,7 +337,7 @@ TypeBoundPredicate::operator= (const TypeBoundPredicate &other)
   reference = other.reference;
   locus = other.locus;
   error_flag = other.error_flag;
-  used_arguments = SubstitutionArgumentMappings::error ();
+  used_arguments = SubstitutionArgumentMappings::empty ();
 
   substitutions.clear ();
   for (const auto &p : other.get_substs ())

diff --git a/gcc/rust/typecheck/rust-tyty-subst.cc b/gcc/rust/typecheck/rust-tyty-subst.cc
index 8ae61f4ee4672e182c693d70e9ecce7dbddf207f..9715b08ad04698c061cae632b2580541590a1426 100644 (file)
--- a/gcc/rust/typecheck/rust-tyty-subst.cc
+++ b/gcc/rust/typecheck/rust-tyty-subst.cc
@@ -236,16 +236,17 @@ SubstitutionArg::as_string () const
 SubstitutionArgumentMappings::SubstitutionArgumentMappings (
   std::vector<SubstitutionArg> mappings,
   std::map<std::string, BaseType *> binding_args, Location locus,
-  ParamSubstCb param_subst_cb, bool trait_item_flag)
+  ParamSubstCb param_subst_cb, bool trait_item_flag, bool error_flag)
   : mappings (mappings), binding_args (binding_args), locus (locus),
-    param_subst_cb (param_subst_cb), trait_item_flag (trait_item_flag)
+    param_subst_cb (param_subst_cb), trait_item_flag (trait_item_flag),
+    error_flag (error_flag)
 {}
 
 SubstitutionArgumentMappings::SubstitutionArgumentMappings (
   const SubstitutionArgumentMappings &other)
   : mappings (other.mappings), binding_args (other.binding_args),
     locus (other.locus), param_subst_cb (nullptr),
-    trait_item_flag (other.trait_item_flag)
+    trait_item_flag (other.trait_item_flag), error_flag (other.error_flag)
 {}
 
 SubstitutionArgumentMappings &
@@ -257,6 +258,7 @@ SubstitutionArgumentMappings::operator= (
   locus = other.locus;
   param_subst_cb = nullptr;
   trait_item_flag = other.trait_item_flag;
+  error_flag = other.error_flag;
 
   return *this;
 }
@@ -264,13 +266,21 @@ SubstitutionArgumentMappings::operator= (
 SubstitutionArgumentMappings
 SubstitutionArgumentMappings::error ()
 {
-  return SubstitutionArgumentMappings ({}, {}, Location (), nullptr, false);
+  return SubstitutionArgumentMappings ({}, {}, Location (), nullptr, false,
+                                      true);
+}
+
+SubstitutionArgumentMappings
+SubstitutionArgumentMappings::empty ()
+{
+  return SubstitutionArgumentMappings ({}, {}, Location (), nullptr, false,
+                                      false);
 }
 
 bool
 SubstitutionArgumentMappings::is_error () const
 {
-  return mappings.size () == 0;
+  return error_flag;
 }
 
 bool

diff --git a/gcc/rust/typecheck/rust-tyty-subst.h b/gcc/rust/typecheck/rust-tyty-subst.h
index c0439f5554bd7556b12882b4794227ab73336df4..37423746f1313424319187928d9b4a50716ae36c 100644 (file)
--- a/gcc/rust/typecheck/rust-tyty-subst.h
+++ b/gcc/rust/typecheck/rust-tyty-subst.h
@@ -109,7 +109,8 @@ public:
                                std::map<std::string, BaseType *> binding_args,
                                Location locus,
                                ParamSubstCb param_subst_cb = nullptr,
-                               bool trait_item_flag = false);
+                               bool trait_item_flag = false,
+                               bool error_flag = false);
 
   SubstitutionArgumentMappings (const SubstitutionArgumentMappings &other);
   SubstitutionArgumentMappings &
@@ -120,6 +121,7 @@ public:
     = default;
 
   static SubstitutionArgumentMappings error ();
+  static SubstitutionArgumentMappings empty ();
 
   bool is_error () const;
 
@@ -161,6 +163,7 @@ private:
   Location locus;
   ParamSubstCb param_subst_cb;
   bool trait_item_flag;
+  bool error_flag;
 };
 
 class SubstitutionRef