1 files changed, 2 insertions, 1 deletions
diff --git a/re.c b/re.c
index 8f4d14dfc9..1a01490e5b 100644
--- a/re.c
+++ b/re.c
@@ -1508,6 +1508,7 @@ static VALUE reg_cache;
 VALUE
 rb_reg_regcomp(VALUE str)
 {
+    volatile VALUE save_str = str;
     if (reg_cache && RREGEXP(reg_cache)->len == RSTRING_LEN(str)
 	&& case_cache == ruby_ignorecase
 	&& kcode_cache == reg_kcode
@@ -1516,7 +1517,7 @@ rb_reg_regcomp(VALUE str)
 
     case_cache = ruby_ignorecase;
     kcode_cache = reg_kcode;
-    return reg_cache = rb_reg_new(RSTRING_PTR(str), RSTRING_LEN(str),
+    return reg_cache = rb_reg_new(RSTRING_PTR(save_str), RSTRING_LEN(save_str),
 				  ruby_ignorecase);
 }