1 files changed, 37 insertions, 11 deletions

diff --git a/string.c b/string.c
index a2287b8f28..8782e41bc2 100644
--- a/string.c
+++ b/string.c
@@ -1913,8 +1913,13 @@ rb_str_sub_bang(argc, argv, str)
 	regs = RMATCH(match)->regs;
 
 	if (iter) {
+	    char *p = RSTRING(str)->ptr; long len = RSTRING(str)->len;
+
 	    rb_match_busy(match);
 	    repl = rb_obj_as_string(rb_yield(rb_reg_nth_match(0, match)));
+	    if (RSTRING(str)->ptr != p || RSTRING(str)->len != len) {
+		rb_raise(rb_eRuntimeError, "string modified");
+	    }
 	    rb_backref_set(match);
 	}
 	else {
@@ -3095,7 +3100,7 @@ tr_setup_table(str, table, init)
 	buf[c & 0xff] = !cflag;
     }
     for (i=0; i<256; i++) {
-	table[i] = table[i]&&buf[i];
+	table[i] = table[i] && buf[i];
     }
 }
 
@@ -3554,6 +3559,17 @@ rb_f_split(argc, argv)
 }
 
 
+static inline void
+str_mod_check(s, p, len)
+    VALUE s;
+    char *p;
+    long len;
+{
+    if (RSTRING(s)->ptr != p || RSTRING(s)->len != len) {
+	rb_raise(rb_eRuntimeError, "string modified");
+    }
+}
+
 /*
  *  call-seq:
  *     str.each(separator=$/) {|substr| block }        => str
@@ -3628,8 +3644,7 @@ rb_str_each_line(argc, argv, str)
 	    line = rb_str_new5(str, s, p - s);
 	    OBJ_INFECT(line, str);
 	    rb_yield(line);
-	    if (RSTRING(str)->ptr != ptr || RSTRING(str)->len != len)
-		rb_raise(rb_eArgError, "string modified");
+	    str_mod_check(str, ptr, len);
 	    s = p;
 	}
     }
@@ -3799,11 +3814,13 @@ rb_str_chomp_bang(argc, argv, str)
 {
     VALUE rs;
     int newline;
-    char *p = RSTRING(str)->ptr;
-    long len = RSTRING(str)->len, rslen;
+    char *p;
+    long len, rslen;
 
     if (rb_scan_args(argc, argv, "01", &rs) == 0) {
+	len = RSTRING(str)->len;
 	if (len == 0) return Qnil;
+	p = RSTRING(str)->ptr;
 	rs = rb_rs;
 	if (rs == rb_default_rs) {
 	  smart_chomp:
@@ -3827,9 +3844,10 @@ rb_str_chomp_bang(argc, argv, str)
 	}
     }
     if (NIL_P(rs)) return Qnil;
-    if (len == 0) return Qnil;
-
     StringValue(rs);
+    len = RSTRING(str)->len;
+    if (len == 0) return Qnil;
+    p = RSTRING(str)->ptr;
     rslen = RSTRING(rs)->len;
     if (rslen == 0) {
 	while (len>0 && p[len-1] == '\n') {
@@ -4277,7 +4295,7 @@ rb_str_crypt(str, salt)
 {
     extern char *crypt();
     VALUE result;
-    char *s;
+    char *s, *cr;
 
     StringValue(salt);
     if (RSTRING(salt)->len < 2)
@@ -4285,7 +4303,10 @@ rb_str_crypt(str, salt)
 
     if (RSTRING(str)->ptr) s = RSTRING(str)->ptr;
     else s = "";
-    result = rb_str_new2(crypt(s, RSTRING(salt)->ptr));
+    cr = crypt(s, RSTRING(salt)->ptr);
+    s = ALLOCA_N(char, strlen(cr));
+    strcpy(s, cr);
+    result = rb_str_new2(s);
     OBJ_INFECT(result, str);
     OBJ_INFECT(result, salt);
     return result;
@@ -4348,14 +4369,17 @@ rb_str_sum(argc, argv, str)
 {
     VALUE vbits;
     int bits;
-    char *p, *pend;
+    char *ptr, *p, *pend;
+    long len;
 
     if (rb_scan_args(argc, argv, "01", &vbits) == 0) {
 	bits = 16;
     }
     else bits = NUM2INT(vbits);
 
-    p = RSTRING(str)->ptr; pend = p + RSTRING(str)->len;
+    ptr = p = RSTRING(str)->ptr;
+    len = RSTRING(str)->len;
+    pend = p + len;
     if (bits > sizeof(long)*CHAR_BIT) {
 	VALUE res = INT2FIX(0);
 	VALUE mod;
@@ -4364,6 +4388,7 @@ rb_str_sum(argc, argv, str)
 	mod = rb_funcall(mod, '-', 1, INT2FIX(1));
 
 	while (p < pend) {
+	    str_mod_check(str, ptr, len);
 	    res = rb_funcall(res, '+', 1, INT2FIX((unsigned int)*p));
 	    p++;
 	}
@@ -4378,6 +4403,7 @@ rb_str_sum(argc, argv, str)
 	    mod = -1;
 	}
 	while (p < pend) {
+	    str_mod_check(str, ptr, len);
 	    res += (unsigned int)*p;
 	    p++;
 	}