1 files changed, 5 insertions, 2 deletions

diff --git a/src/ftfont.c b/src/ftfont.c
index 5037d54bc2f..4e313a89021 100644
--- a/src/ftfont.c
+++ b/src/ftfont.c
@@ -2385,8 +2385,8 @@ static Lisp_Object
 ftfont_shape_by_flt (Lisp_Object lgstring, struct font *font,
                      FT_Face ft_face, OTF *otf, FT_Matrix *matrix)
 {
-  EMACS_UINT len = LGSTRING_GLYPH_LEN (lgstring);
-  EMACS_UINT i;
+  EMACS_INT len = LGSTRING_GLYPH_LEN (lgstring);
+  EMACS_INT i;
   struct MFLTFontFT flt_font_ft;
   MFLT *flt = NULL;
   int with_variation_selector = 0;
@@ -2412,7 +2412,10 @@ ftfont_shape_by_flt (Lisp_Object lgstring, struct font *font,
       if (CHAR_VARIATION_SELECTOR_P (c))
         with_variation_selector++;
     }
+
   len = i;
+  lint_assume (len <= TYPE_MAXIMUM (EMACS_INT) - 2);
+
   if (with_variation_selector)
     {
       setup_otf_gstring (len);