fix overflow error like #2244 on MRB_WORD_BOXING

include/mruby/value.h

@@ -27,8 +27,13 @@
 # else
    typedef int64_t mrb_int;
 #  define MRB_INT_BIT 64
-#  define MRB_INT_MIN INT64_MIN
-#  define MRB_INT_MAX INT64_MAX
+#  ifdef MRB_WORD_BOXING
+#   define MRB_INT_MIN (INT64_MIN>>MRB_FIXNUM_SHIFT)
+#   define MRB_INT_MAX (INT64_MAX>>MRB_FIXNUM_SHIFT)
+#  else
+#   define MRB_INT_MIN INT64_MIN
+#   define MRB_INT_MAX INT64_MAX
+#  endif
 #  define PRIdMRB_INT PRId64
 #  define PRIiMRB_INT PRIi64
 #  define PRIoMRB_INT PRIo64
@@ -36,6 +41,9 @@
 #  define PRIXMRB_INT PRIX64
 # endif
 #elif defined(MRB_INT16)
+# ifdef MRB_WORD_BOXING
+# error "MRB_INT16 is too small for MRB_WORD_BOXING."
+# endif
   typedef int16_t mrb_int;
 # define MRB_INT_BIT 16
 # define MRB_INT_MIN INT16_MIN
@@ -43,8 +51,13 @@
 #else
   typedef int32_t mrb_int;
 # define MRB_INT_BIT 32
-# define MRB_INT_MIN INT32_MIN
-# define MRB_INT_MAX INT32_MAX
+# ifdef MRB_WORD_BOXING
+#  define MRB_INT_MIN (INT32_MIN>>MRB_FIXNUM_SHIFT)
+#  define MRB_INT_MAX (INT32_MAX>>MRB_FIXNUM_SHIFT)
+# else
+#  define MRB_INT_MIN INT32_MIN
+#  define MRB_INT_MAX INT32_MAX
+# endif
 # define PRIdMRB_INT PRId32
 # define PRIiMRB_INT PRIi32
 # define PRIoMRB_INT PRIo32

src/numeric.c

@@ -687,7 +687,11 @@ int_to_i(mrb_state *mrb, mrb_value num)
   return num;
 }
 
+#ifdef MRB_FIXNUM_SHIFT
+#define SQRT_INT_MAX ((mrb_int)1<<((MRB_INT_BIT-1-MRB_FIXNUM_SHIFT)/2))
+#else
 #define SQRT_INT_MAX ((mrb_int)1<<((MRB_INT_BIT-1)/2))
+#endif
 /*tests if N*N would overflow*/
 #define FIT_SQRT_INT(n) (((n)<SQRT_INT_MAX)&&((n)>=-SQRT_INT_MAX))
 
@@ -705,7 +709,7 @@ mrb_fixnum_mul(mrb_state *mrb, mrb_value x, mrb_value y)
     if (FIT_SQRT_INT(a) && FIT_SQRT_INT(b))
       return mrb_fixnum_value(a*b);
     c = a * b;
-    if (a != 0 && c/a != b) {
+    if ((a != 0 && c/a != b) || !FIXABLE(c)) {
       return mrb_float_value(mrb, (mrb_float)a*(mrb_float)b);
     }
     return mrb_fixnum_value(c);

test/driver.c

@@ -109,15 +109,9 @@ main(int argc, char **argv)
 
   mrbtest = mrb_define_module(mrb, "Mrbtest");
 
-#ifdef MRB_WORD_BOXING
-  mrb_define_const(mrb, mrbtest, "FIXNUM_MAX", mrb_fixnum_value(MRB_INT_MAX >> MRB_FIXNUM_SHIFT));
-  mrb_define_const(mrb, mrbtest, "FIXNUM_MIN", mrb_fixnum_value(MRB_INT_MIN >> MRB_FIXNUM_SHIFT));
-  mrb_define_const(mrb, mrbtest, "FIXNUM_BIT", mrb_fixnum_value(MRB_INT_BIT >> MRB_FIXNUM_SHIFT));
-#else
   mrb_define_const(mrb, mrbtest, "FIXNUM_MAX", mrb_fixnum_value(MRB_INT_MAX));
   mrb_define_const(mrb, mrbtest, "FIXNUM_MIN", mrb_fixnum_value(MRB_INT_MIN));
   mrb_define_const(mrb, mrbtest, "FIXNUM_BIT", mrb_fixnum_value(MRB_INT_BIT));
-#endif
 
   mrb_init_mrbtest(mrb);
   ret = eval_test(mrb);