gccrs: Resolve nested macro definition

We need to collect the early resolver's macros error to emit them at a
later stage after further expansion in order to retrieve macros defined
by other macro invocations.
Register some mappings for macro invocations and macro definitions.

gcc/rust/ChangeLog:

	* resolve/rust-early-name-resolver-2.0.cc (Early::visit):
	Collect error instead of emitting it. Also add invocation
	registration.
	* resolve/rust-early-name-resolver-2.0.h (std::function<void):
	Add type definition for collection.
	* resolve/rust-toplevel-name-resolver-2.0.cc (TopLevel::visit):
	Register macro rule definition in mappings.
	* rust-session-manager.cc (Session::expansion): Add macro
	resolve error collection.

Signed-off-by: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>

1 files changed, 10 insertions, 1 deletions

diff --git a/gcc/rust/rust-session-manager.cc b/gcc/rust/rust-session-manager.cc
index 1c5d729..8911e7d 100644
--- a/gcc/rust/rust-session-manager.cc
+++ b/gcc/rust/rust-session-manager.cc
@@ -874,6 +874,7 @@ Session::expansion (AST::Crate &crate)
   /* expand by calling cxtctxt object's monotonic_expander's expand_crate
    * method. */
   MacroExpander expander (crate, cfg, *this);
+  std::vector<Resolver2_0::ResolveError> macro_errors;
 
   while (!fixed_point_reached && iterations < cfg.recursion_limit)
     {
@@ -882,7 +883,11 @@ Session::expansion (AST::Crate &crate)
       auto ctx = Resolver2_0::NameResolutionContext ();
 
       if (flag_name_resolution_2_0)
-	Resolver2_0::Early (ctx).go (crate);
+	{
+	  Resolver2_0::Early early (ctx);
+	  early.go (crate);
+	  macro_errors = early.get_macro_resolve_errors ();
+	}
       else
 	Resolver::EarlyNameResolver ().go (crate);
 
@@ -896,6 +901,10 @@ Session::expansion (AST::Crate &crate)
 	break;
     }
 
+  // Fixed point reached: Emit unresolved macros error
+  for (auto &error : macro_errors)
+    error ();
+
   if (iterations == cfg.recursion_limit)
     {
       auto &last_invoc = expander.get_last_invocation ();