rust/lex: skip broken string expression ...

... when the matching quote is not found on the same line

this could unstuck the string parser when the parser could not advance
the parsing position

1 files changed, 32 insertions, 0 deletions

diff --git a/gcc/rust/lex/rust-lex.cc b/gcc/rust/lex/rust-lex.cc
index ea09ac2..023b676 100644
--- a/gcc/rust/lex/rust-lex.cc
+++ b/gcc/rust/lex/rust-lex.cc
@@ -1856,6 +1856,35 @@ Lexer::parse_raw_identifier (Location loc)
     }
 }
 
+// skip broken string input (unterminated strings)
+void
+Lexer::skip_broken_string_input (int current_char)
+{
+  while (current_char != '"' && current_char != EOF)
+    {
+      if (current_char == '\n')
+	{
+	  current_line++;
+	  current_column = 1;
+	}
+      else
+	{
+	  current_column++;
+	}
+      skip_input ();
+      current_char = peek_input ();
+    }
+  if (current_char == '"')
+    {
+      current_column++;
+
+      skip_input ();
+      current_char = peek_input ();
+    }
+  rust_debug ("skipped to %d:%d due to bad quotes", current_line,
+	      current_column);
+}
+
 // Parses a unicode string.
 TokenPtr
 Lexer::parse_string (Location loc)
@@ -1903,6 +1932,9 @@ Lexer::parse_string (Location loc)
   if (current_char32.value == '\n')
     {
       rust_error_at (get_current_location (), "unended string literal");
+      // by this point, the parser will stuck at this position due to
+      // undetermined string termination. we now need to unstuck the parser
+      skip_broken_string_input (current_char32.value);
     }
   else if (current_char32.value == '"')
     {