(IT_EXPAND_MATRIX_WIDTH): New macro. Do not

expand matrix width for overflow in zero-width area.
(append_glyph, append_composite_glyph, produce_image_glyph)
(append_stretch_glyph): Use it to avoid loop in redisplay.
(note_mode_line_or_margin_highlight): Don't let help-echo from
string override help-echo from image map.

1 files changed, 30 insertions, 26 deletions

diff --git a/src/xdisp.c b/src/xdisp.c
index 04851288e46..4f82767906c 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -18269,6 +18269,19 @@ draw_glyphs (w, x, row, area, start, end, hl, overlaps_p)
   return x_reached;
 }
 
+/* Expand row matrix if too narrow.  Don't expand if area
+   is not present.  */
+
+#define IT_EXPAND_MATRIX_WIDTH(it, area)                \
+  {                                                     \
+    if (!fonts_changed_p                                \
+        && (it->glyph_row->glyphs[area]                 \
+            < it->glyph_row->glyphs[area + 1]))         \
+      {                                                 \
+        it->w->ncols_scale_factor++;                    \
+        fonts_changed_p = 1;                            \
+      }                                                 \
+  }
 
 /* Store one glyph for IT->char_to_display in IT->glyph_row.
    Called from x_produce_glyphs when IT->glyph_row is non-null.  */
@@ -18306,11 +18319,8 @@ append_glyph (it)
       glyph->font_type = FONT_TYPE_UNKNOWN;
       ++it->glyph_row->used[area];
     }
-  else if (!fonts_changed_p)
-    {
-      it->w->ncols_scale_factor++;
-      fonts_changed_p = 1;
-    }
+  else
+    IT_EXPAND_MATRIX_WIDTH (it, area);
 }
 
 /* Store one glyph for the composition IT->cmp_id in IT->glyph_row.
@@ -18348,11 +18358,8 @@ append_composite_glyph (it)
       glyph->font_type = FONT_TYPE_UNKNOWN;
       ++it->glyph_row->used[area];
     }
-  else if (!fonts_changed_p)
-    {
-      it->w->ncols_scale_factor++;
-      fonts_changed_p = 1;
-    }
+  else
+    IT_EXPAND_MATRIX_WIDTH (it, area);
 }
 
 
@@ -18522,11 +18529,8 @@ produce_image_glyph (it)
           glyph->font_type = FONT_TYPE_UNKNOWN;
           ++it->glyph_row->used[area];
         }
-      else if (!fonts_changed_p)
-        {
-          it->w->ncols_scale_factor++;
-          fonts_changed_p = 1;
-        }
+      else
+        IT_EXPAND_MATRIX_WIDTH (it, area);
     }
 }
 
@@ -18570,11 +18574,8 @@ append_stretch_glyph (it, object, width, height, ascent)
       glyph->font_type = FONT_TYPE_UNKNOWN;
       ++it->glyph_row->used[area];
     }
-  else if (!fonts_changed_p)
-    {
-      it->w->ncols_scale_factor++;
-      fonts_changed_p = 1;
-    }
+  else
+    IT_EXPAND_MATRIX_WIDTH (it, area);
 }
 
 
@@ -20947,13 +20948,16 @@ note_mode_line_or_margin_highlight (w, x, y, area)
       /* If we're on a string with `help-echo' text property, arrange
          for the help to be displayed.  This is done by setting the
          global variable help_echo_string to the help string.  */
-      help = Fget_text_property (pos, Qhelp_echo, string);
-      if (!NILP (help))
+      if (NILP (help))
         {
-          help_echo_string = help;
-          XSETWINDOW (help_echo_window, w);
-          help_echo_object = string;
-          help_echo_pos = charpos;
+          help = Fget_text_property (pos, Qhelp_echo, string);
+          if (!NILP (help))
+            {
+              help_echo_string = help;
+              XSETWINDOW (help_echo_window, w);
+              help_echo_object = string;
+              help_echo_pos = charpos;
+            }
         }
 
       if (NILP (pointer))