1 files changed, 14 insertions, 0 deletions
diff --git a/ext/-test-/string/modify.c b/ext/-test-/string/modify.c
new file mode 100644
index 0000000000..a6930051b6
--- /dev/null
+++ b/ext/-test-/string/modify.c
@@ -0,0 +1,14 @@
+#include "ruby.h"
+
+VALUE
+bug_str_modify(VALUE str)
+{
+    rb_str_modify(str);
+    return str;
+}
+
+void
+Init_modify(VALUE klass)
+{
+    rb_define_method(klass, "modify!", bug_str_modify, 0);
+}