Merge #1163

1163: rust-session-manager: handle `crate_name` attribute r=philberty a=liushuyu

- rust-session-manager: handle `crate_name` attribute

Fix #789 properly

Co-authored-by: liushuyu <liushuyu011@gmail.com>

Author: bors[bot]

gcc/rust/rust-session-manager.cc

@@ -405,7 +405,10 @@ Session::handle_option (
 	{
 	  auto error = Error (Location (), std::string ());
 	  if ((ret = validate_crate_name (arg, error)))
-	    options.set_crate_name (arg);
+	    {
+	      options.set_crate_name (arg);
+	      options.crate_name_set_manually = true;
+	    }
 	  else
 	    {
 	      rust_assert (!error.message.empty ());
@@ -553,19 +556,9 @@ Session::parse_files (int num_files, const char **files)
 	filename = files[0];
 
       auto crate_name = infer_crate_name (filename);
-      Error error ((Location ()), std::string ());
       rust_debug ("inferred crate name: %s", crate_name.c_str ());
-      if (!validate_crate_name (crate_name, error))
-	{
-	  // fake a linemapping so that we can show the filename
-	  linemap->start_file (filename, 0);
-	  linemap->start_line (0, 1);
-	  error.emit_error ();
-	  rust_inform (linemap->get_location (0),
-		       "crate name inferred from this file");
-	  linemap->stop ();
-	  return;
-	}
+      // set the preliminary crate name here
+      // we will figure out the real crate name in `handle_crate_name`
       options.set_crate_name (crate_name);
     }
 
@@ -582,6 +575,57 @@ Session::parse_files (int num_files, const char **files)
    * per-file. */
 }
 
+void
+Session::handle_crate_name (AST::Crate parsed_crate)
+{
+  auto mappings = Analysis::Mappings::get ();
+  auto crate_name_changed = false;
+  auto error = Error (Location (), std::string ());
+
+  for (const auto &attr : parsed_crate.inner_attrs)
+    {
+      if (attr.get_path () != "crate_name")
+	continue;
+      if (!attr.has_attr_input ())
+	{
+	  rust_error_at (attr.get_locus (),
+			 "%<crate_name%> accepts one argument");
+	  continue;
+	}
+
+      auto &literal
+	= static_cast<AST::AttrInputLiteral &> (attr.get_attr_input ());
+      const auto &msg_str = literal.get_literal ().as_string ();
+      if (!validate_crate_name (msg_str, error))
+	{
+	  error.locus = attr.get_locus ();
+	  error.emit_error ();
+	  continue;
+	}
+
+      auto options = Session::get_instance ().options;
+      if (options.crate_name_set_manually && (options.crate_name != msg_str))
+	{
+	  rust_error_at (attr.get_locus (),
+			 "%<-frust-crate-name%> and %<#[crate_name]%> are "
+			 "required to match, but %qs does not match %qs",
+			 options.crate_name.c_str (), msg_str.c_str ());
+	}
+      crate_name_changed = true;
+      options.set_crate_name (msg_str);
+      mappings->set_crate_name (mappings->get_current_crate (), msg_str);
+    }
+
+  options.crate_name_set_manually |= crate_name_changed;
+  if (!options.crate_name_set_manually
+      && !validate_crate_name (options.crate_name, error))
+    {
+      error.emit_error ();
+      rust_inform (linemap->get_location (0),
+		   "crate name inferred from this file");
+    }
+}
+
 // Parses a single file with filename filename.
 void
 Session::parse_file (const char *filename)
@@ -606,6 +650,9 @@ Session::parse_file (const char *filename)
   auto mappings = Analysis::Mappings::get ();
   mappings->insert_ast_crate (&parsed_crate);
 
+  // handle crate name
+  handle_crate_name (parsed_crate);
+
   if (options.dump_option_enabled (CompileOptions::LEXER_DUMP))
     {
       dump_lex (parser);

gcc/rust/rust-session-manager.h

@@ -182,6 +182,7 @@ struct CompileOptions
    * pointer width, vendor */
   TargetOptions target_data;
   std::string crate_name;
+  bool crate_name_set_manually = false;
   bool enable_test = false;
   bool debug_assertions = false;
   bool proc_macro = false;
@@ -270,6 +271,7 @@ struct Session
 		      const struct cl_option_handlers *handlers);
   void parse_files (int num_files, const char **files);
   void init_options ();
+  void handle_crate_name (AST::Crate parsed_crate);
 
   /* This function saves the filename data into the session manager using the
    * `move` semantics, and returns a C-style string referencing the input

gcc/rust/util/rust-hir-map.h

@@ -88,6 +88,19 @@ class Mappings
     return true;
   }
 
+  // set crate name mid-compilation
+  // don't use this if setting crate name before Session::parse_files
+  bool set_crate_name (CrateNum crate_num, std::string name)
+  {
+    rust_assert (!name.empty ());
+    auto it = crate_names.find (crate_num);
+    if (it == crate_names.end ())
+      return false;
+
+    it->second.assign (name);
+    return true;
+  }
+
   std::string get_current_crate_name () const
   {
     std::string name;

gcc/testsuite/rust/compile/attr-mismatch-crate-name.rs

@@ -0,0 +1,4 @@
+// { dg-additional-options "-fdump-tree-gimple" }
+#![crate_name = "specified_name"]
+// { dg-final { scan-tree-dump-times {specified_name::main} 1 gimple } }
+fn main() {}

gcc/testsuite/rust/compile/mismatch-crate-name.rs

@@ -0,0 +1,4 @@
+// { dg-additional-options "-frust-crate=another_name" }
+#![crate_name = "legit_name"]
+// { dg-error ".-frust-crate-name. and .#.crate_name.. are required to match, but .another_name. does not match .legit_name." "" { target *-*-* } .-1 }
+fn main() {}