1 files changed, 21 insertions, 1 deletions

diff --git a/src/dispextern.h b/src/dispextern.h
index 8644ce26d13..1df769a8f99 100644
--- a/src/dispextern.h
+++ b/src/dispextern.h
@@ -384,6 +384,7 @@ struct glyph
       glyph standing for newline at end of line    0
       empty space after the end of the line       -1
       overlay arrow on a TTY                      -1
+      glyph displaying line number                -1
       glyph at EOB that ends in a newline         -1
       left truncation glyphs:                     -1
       right truncation/continuation glyphs        next buffer position
@@ -2537,7 +2538,12 @@ struct it
      Do NOT use !BUFFERP (it.object) as a test whether we are
      iterating over a string; use STRINGP (it.string) instead.
 
-     Position is the current iterator position in object.  */
+     Position is the current iterator position in object.
+
+     The 'position's CHARPOS is copied to glyph->charpos of the glyph
+     produced by PRODUCE_GLYPHS, so any artificial value documented
+     under 'struct glyph's 'charpos' member can also be found in the
+     'position' member here.  */
   Lisp_Object object;
   struct text_pos position;
 
@@ -2621,6 +2627,20 @@ struct it
      coordinate is past first_visible_x.  */
   int hpos;
 
+  /* Current line number, zero-based.  */
+  ptrdiff_t lnum;
+
+  /* The byte position corresponding to lnum.  */
+  ptrdiff_t lnum_bytepos;
+
+  /* The width, in columns and in pixels, needed for display of the
+     line numbers, or zero if not computed.  */
+  int lnum_width;
+  int lnum_pixel_width;
+
+  /* The line number of point's line, or zero if not computed yet.  */
+  ptrdiff_t pt_lnum;
+
   /* Left fringe bitmap number (enum fringe_bitmap_type).  */
   unsigned left_user_fringe_bitmap : FRINGE_ID_BITS;