* lib.c (chr_str_set): Check for literal strings.

2 files changed, 9 insertions, 0 deletions

diff --git a/ChangeLog b/ChangeLog
index 9bfabebe..c778a0e2 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,9 @@
 2015-05-11  Kaz Kylheku  <kaz@kylheku.com>
 
+	* lib.c (chr_str_set): Check for literal strings.
+
+2015-05-11  Kaz Kylheku  <kaz@kylheku.com>
+
 	Fix argument count checking regression.
 
 	* eval.c (apply): Revert some changes from 2015-03-13
diff --git a/lib.c b/lib.c
index ad83e91a..46e445ca 100644
--- a/lib.c
+++ b/lib.c
@@ -3463,6 +3463,11 @@ val chr_str_set(val str, val ind, val chr)
 {
   cnum index = c_num(ind);
 
+  if (is_lit(str)) {
+    uw_throwf(error_s, lit("chr-str-set: cannot modify literal string ~s"),
+              str, nao);
+  }
+
   if (index < 0) {
     ind = plus(length_str(str), ind);
     index = c_num(ind);