Avoid crashes in 'font-at' after 'set-fontset-font'

* src/fontset.c (free_realized_fontsets): Call
recompute_basic_faces, so that the basic faces are available to
any Lisp that calls this function, e.g. via set-fontset-font.
(Bug#29632)

1 files changed, 4 insertions, 0 deletions

diff --git a/src/fontset.c b/src/fontset.c
index 35586ad5c7d..985800103d2 100644
--- a/src/fontset.c
+++ b/src/fontset.c
@@ -1325,6 +1325,10 @@ free_realized_fontsets (Lisp_Object base)
       if (CHAR_TABLE_P (this) && EQ (FONTSET_BASE (this), base))
         {
           Fclear_face_cache (Qt);
+          /* This is in case some Lisp calls this function and then
+             proceeds with calling some other function, like font-at,
+             which needs the basic faces.  */
+          recompute_basic_faces (XFRAME (FONTSET_FRAME (this)));
           break;
         }
     }