parser: accept #line NUM

* src/scan-gram.l (scanner): Accept '#line NUM'.
(handle_syncline): Adjust to the possible missing file name.

1 files changed, 13 insertions, 9 deletions

diff --git a/src/scan-gram.l b/src/scan-gram.l
index fd6458fa..5e78cb9b 100644
--- a/src/scan-gram.l
+++ b/src/scan-gram.l
@@ -157,7 +157,7 @@ splice	 (\\[ \f\t\v]*\n)*
 
   /* #line directives are not documented, and may be withdrawn or
      modified in future versions of Bison.  */
-  ^"#line "{int}" \"".*"\"\n" {
+  ^"#line "{int}(" \"".*"\"")?"\n" {
     handle_syncline (yytext + sizeof "#line " - 1, *loc);
   }
 }
@@ -845,23 +845,27 @@ convert_ucn_to_byte (char const *ucn)
 }
 
 
-/*----------------------------------------------------------------.
-| Handle '#line INT "FILE"'.  ARGS has already skipped '#line '.  |
-`----------------------------------------------------------------*/
+/*---------------------------------------------------------------------.
+| Handle '#line INT( "FILE")?\n'.  ARGS has already skipped '#line '.  |
+`---------------------------------------------------------------------*/
 
 static void
 handle_syncline (char *args, location loc)
 {
-  char *after_num;
-  unsigned long int lineno = strtoul (args, &after_num, 10);
-  char *file = mbschr (after_num, '"') + 1;
-  *mbschr (file, '"') = '\0';
+  char *file;
+  unsigned long int lineno = strtoul (args, &file, 10);
   if (INT_MAX <= lineno)
     {
       warn_at (loc, _("line number overflow"));
       lineno = INT_MAX;
     }
-  current_file = uniqstr_new (file);
+
+  file = mbschr (file, '"');
+  if (file)
+    {
+      *mbschr (file + 1, '"') = '\0';
+      current_file = uniqstr_new (file + 1);
+    }
   boundary_set (&scanner_cursor, current_file, lineno, 1);
 }