diff --git a/ChangeLog b/ChangeLog
index 1a5d821ca3..4b48b075ab 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Wed Jun  2 12:41:53 2004  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* io.c (rb_io_gets_m): set lastline ($_) even when read line is
+	  nil.  [ruby-dev:23663]
+
 Fri May 28 11:20:31 2004  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* eval.c (rb_eval): bad influence on frame node.
diff --git a/bignum.c b/bignum.c
index 31a5f58c24..510860c03c 100644
--- a/bignum.c
+++ b/bignum.c
@@ -982,10 +982,11 @@ rb_big_eq(x, y)
 	break;
       case T_FLOAT:
         {
-	    double a, b;
+	    volatile double a, b;
 
 	    a = RFLOAT(y)->value;
 	    b = rb_big2dbl(x);
+	    if (isnan(a) || isnan(b)) return Qfalse;
 	    return (a == b)?Qtrue:Qfalse;
 	}
       default:
diff --git a/file.c b/file.c
index a32a76dfad..435b623e3c 100644
--- a/file.c
+++ b/file.c
@@ -3970,7 +3970,7 @@ path_check_1(path)
 #ifdef S_ISVTX
 	    && !(st.st_mode & S_ISVTX)
 #endif
-	    ) {
+	    && !access(p0, W_OK)) {
 	    rb_warn("Insecure world writable dir %s, mode 0%o", p0, st.st_mode);
 	    if (p) *p = '/';
 	    return 0;
diff --git a/io.c b/io.c
index 7f6b8f438e..52b4cfb05c 100644
--- a/io.c
+++ b/io.c
@@ -1367,10 +1367,8 @@ rb_io_gets_m(argc, argv, io)
     }
     GetOpenFile(io, fptr);
     str = rb_io_getline(rs, fptr);
+    rb_lastline_set(str);
 
-    if (!NIL_P(str)) {
-	rb_lastline_set(str);
-    }
     return str;
 }
 
diff --git a/numeric.c b/numeric.c
index 4c97fbe526..763e4d2ba6 100644
--- a/numeric.c
+++ b/numeric.c
@@ -818,7 +818,7 @@ static VALUE
 flo_eq(x, y)
     VALUE x, y;
 {
-    double a, b;
+    volatile double a, b;
 
     switch (TYPE(y)) {
       case T_FIXNUM: