1 files changed, 58 insertions, 2 deletions

diff --git a/src/xfaces.c b/src/xfaces.c
index df078227c8a..643f4365896 100644
--- a/src/xfaces.c
+++ b/src/xfaces.c
@@ -6071,8 +6071,42 @@ realize_gui_face (struct face_cache *cache, Lisp_Object attrs[LFACE_VECTOR_SIZE]
             emacs_abort ();
         }
       if (! FONT_OBJECT_P (attrs[LFACE_FONT_INDEX]))
-        attrs[LFACE_FONT_INDEX]
-          = font_load_for_lface (f, attrs, attrs[LFACE_FONT_INDEX]);
+        {
+          Lisp_Object spec = copy_font_spec (attrs[LFACE_FONT_INDEX]);
+#define   MAYBE_UNSET_ATTRIBUTE(ATTR)                   \
+          if (realize_gui_face_ignored_spec_attributes  \
+              & (1 << FONT_##ATTR##_INDEX))             \
+            ASET (spec, FONT_##ATTR##_INDEX, Qnil);
+          /* The default value of
+             realize_gui_face_ignored_spec_attributes unsets the
+             weight, slant and width in spec.  The best possible
+             values for these attributes is determined in
+             font_find_for_lface, called by font_load_for_lface, when
+             the candidate list returned by font_list_entities is
+             sorted by font_select_entity (which calls
+             font_sort_entities, which calls font_score).  If these
+             attributes are not unset here, the candidate font list
+             returned by font_list_entities only contains fonts that
+             are exact matches for these weight, slant and width
+             attributes, which leads to suboptimal or wrong font
+             choices.  See bug#59347.  */
+          MAYBE_UNSET_ATTRIBUTE (WEIGHT);
+          MAYBE_UNSET_ATTRIBUTE (SLANT);
+          MAYBE_UNSET_ATTRIBUTE (WIDTH);
+          /* Also allow unsetting other attributes for debugging
+             purposes.  */
+          MAYBE_UNSET_ATTRIBUTE (FAMILY);
+          MAYBE_UNSET_ATTRIBUTE (FOUNDRY);
+          MAYBE_UNSET_ATTRIBUTE (REGISTRY);
+          MAYBE_UNSET_ATTRIBUTE (ADSTYLE);
+          MAYBE_UNSET_ATTRIBUTE (SIZE);
+          MAYBE_UNSET_ATTRIBUTE (DPI);
+          MAYBE_UNSET_ATTRIBUTE (SPACING);
+          MAYBE_UNSET_ATTRIBUTE (AVGWIDTH);
+          MAYBE_UNSET_ATTRIBUTE (EXTRA);
+#undef    MAYBE_UNSET_ATTRIBUTE
+          attrs[LFACE_FONT_INDEX] = font_load_for_lface (f, attrs, spec);
+        }
       if (FONT_OBJECT_P (attrs[LFACE_FONT_INDEX]))
         {
           face->font = XFONT_OBJECT (attrs[LFACE_FONT_INDEX]);
@@ -7360,6 +7394,28 @@ Lisp programs that change the value of this variable should also
 clear the face cache, see `clear-face-cache'.  */);
   face_near_same_color_threshold = 30000;
 
+  DEFVAR_INT ("realize-gui-face-ignored-spec-attributes",
+              realize_gui_face_ignored_spec_attributes,
+              doc: /* Ignored font-spec attributes in realize_gui_face.
+
+The value is an integer number and represents a bit mask.
+The attribute corresponding to each bit that is set is cleared in
+realize_gui_face.  The bits are: 1 = :foundry, 2 = :family,
+3 = :adstyle, 4 = :registry, 5 = :weight, 6 = :slant, 7 = :width,
+8 = :size, 9 = :dpi, 10 = :spacing, 11 = :avgwidth, 12 = extra
+attributes (:name, :script, :lang and :otf).
+
+Bits 5 to 7 are set in the default value.  When these bits are not
+set, and when the font chosen for the default face has a weight, slant
+or width that is not supported by other available fonts on the system,
+such as 'medium', Emacs may select suboptimal fonts for other faces.
+
+There is no reason to change that value except for debugging purposes.  */);
+  realize_gui_face_ignored_spec_attributes =
+    (1 << FONT_WEIGHT_INDEX) |
+    (1 << FONT_SLANT_INDEX) |
+    (1 << FONT_WIDTH_INDEX);
+
 #ifdef HAVE_WINDOW_SYSTEM
   defsubr (&Sbitmap_spec_p);
   defsubr (&Sx_list_fonts);