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-rw-r--r--stdlib/random.c26
1 files changed, 18 insertions, 8 deletions
diff --git a/stdlib/random.c b/stdlib/random.c
index fb32b36b87..473a5b13d3 100644
--- a/stdlib/random.c
+++ b/stdlib/random.c
@@ -122,12 +122,14 @@ static int seps[MAX_TYPES] = { SEP_0, SEP_1, SEP_2, SEP_3, SEP_4 };
 static long int randtbl[DEG_3 + 1] =
   {
     TYPE_3,
-    -851904987, -43806228, -2029755270, 1390239686, -1912102820,
-    -485608943, 1969813258, -1590463333, -1944053249, 455935928, 508023712,
-    -1714531963, 1800685987, -2015299881, 654595283, -1149023258,
-    -1470005550, -1143256056, -1325577603, -1568001885, 1275120390,
-    -607508183, -205999574, -1696891592, 1492211999, -1528267240,
-    -952028296, -189082757, 362343714, 1424981831, 2039449641,
+
+    -1726662223, 379960547, 1735697613, 1040273694, 1313901226, 
+    1627687941, -179304937, -2073333483, 1780058412, -1989503057, 
+    -615974602, 344556628, 939512070, -1249116260, 1507946756, 
+    -812545463, 154635395, 1388815473, -1926676823, 525320961, 
+    -1009028674, 968117788, -123449607, 1284210865, 435012392, 
+    -2017506339, -911064859, -370259173, 1132637927, 1398500161, 
+    -205601318, 
   };
 
 /* FPTR and RPTR are two pointers into the state info, a front and a rear
@@ -179,11 +181,19 @@ DEFUN(__srandom, (x), unsigned int x)
     {
       register long int i;
       for (i = 1; i < rand_deg; ++i)
-	state[i] = (1103515145 * state[i - 1]) + 12345;
+	{
+	  /* This does:
+	       state[i] = (16807 * state[i - 1]) % 2147483647;
+	     but avoids overflowing 31 bits.  */
+	  long int hi = state[i - 1] / 127773;
+	  long int lo = state[i - 1] % 127773;
+	  long int test = 16807 * lo - 2836 * hi;
+	  state[i] = test + (test < 0 ? 2147483647 : 0);
+	}
       fptr = &state[rand_sep];
       rptr = &state[0];
       for (i = 0; i < 10 * rand_deg; ++i)
-	(void) __random();
+	(void) __random ();
     }
 }