compiler: tweaks for importing inline function bodies

    
    Track whether we've seen an error when importing a function; we will
    use error tracking to avoid knock-on errors.
    
    Stop importing identifiers at a ')'.
    
    Provide a way to adjust the indentation level while importing.
    
    Reviewed-on: https://go-review.googlesource.com/c/150072

From-SVN: r266536

gcc/go/gofrontend/MERGE

-267d91b41571329e71a88f56df46444b305482da
+b013405f2c66596c47cb9be493c798db1087c0f0
 
 The first line of this file holds the git revision number of the last
 merge done from the gofrontend repository.

gcc/go/gofrontend/import.cc

@@ -1225,7 +1225,7 @@ Import::read_identifier()
   while (true)
     {
       c = stream->peek_char();
-      if (c == -1 || c == ' ' || c == '\n' || c == ';')
+      if (c == -1 || c == ' ' || c == '\n' || c == ';' || c == ')')
 	break;
       ret += c;
       stream->advance(1);
@@ -1450,7 +1450,7 @@ Import_function_body::read_identifier()
   for (size_t i = start; i < this->body_.length(); i++)
     {
       int c = static_cast<unsigned char>(this->body_[i]);
-      if (c == ' ' || c == '\n' || c == ';')
+      if (c == ' ' || c == '\n' || c == ';' || c == ')')
 	{
 	  this->off_ = i;
 	  return this->body_.substr(start, i - start);

gcc/go/gofrontend/import.h

@@ -554,7 +554,7 @@ class Import_function_body : public Import_expression
 		       const std::string& body, size_t off, Block* block,
 		       int indent)
     : gogo_(gogo), imp_(imp), named_object_(named_object), body_(body),
-      off_(off), block_(block), indent_(indent)
+      off_(off), block_(block), indent_(indent), saw_error_(false)
   { }
 
   // The IR.
@@ -597,6 +597,16 @@ class Import_function_body : public Import_expression
   indent() const
   { return this->indent_; }
 
+  // Increment the indentation level.
+  void
+  increment_indent()
+  { ++this->indent_; }
+
+  // Decrement the indentation level.
+  void
+  decrement_indent()
+  { --this->indent_; }
+
   // The name of the function we are parsing.
   const std::string&
   name() const;
@@ -652,6 +662,16 @@ class Import_function_body : public Import_expression
   ifb()
   { return this; }
 
+  // Return whether we have seen an error.
+  bool
+  saw_error() const
+  { return this->saw_error_; }
+
+  // Record that we have seen an error.
+  void
+  set_saw_error()
+  { this->saw_error_ = true; }
+
  private:
   // The IR.
   Gogo* gogo_;