diff --git a/src/spell.c b/src/spell.c
index 607bb39..04e4af6 100644
--- a/src/spell.c
+++ b/src/spell.c
@@ -4367,7 +4367,7 @@
     regprog_T   *rp = synblock->b_cap_prog;
     char_u	*re;
 
-    if (*synblock->b_p_spc == NUL)
+    if (synblock->b_p_spc == NULL || *synblock->b_p_spc == NUL)
 	synblock->b_cap_prog = NULL;
     else
     {