From 5eb47f8ed920a909eb6999ae8fb683d688c48ec5 Mon Sep 17 00:00:00 2001
From: Andreas Rumpf <rumpf_a@web.de>
Date: Sun, 2 Jun 2019 14:24:38 +0200
Subject: [PATCH] fixes #11369 (#11381)

---
 lib/pure/strutils.nim     | 20 ++++++++++----------
 tests/stdlib/tstrutil.nim |  7 +++++++
 2 files changed, 17 insertions(+), 10 deletions(-)

diff --git a/lib/pure/strutils.nim b/lib/pure/strutils.nim
index 7e6d31727e..114141e458 100644
--- a/lib/pure/strutils.nim
+++ b/lib/pure/strutils.nim
@@ -892,14 +892,14 @@ proc toBin*(x: BiggestInt, len: Positive): string {.noSideEffect,
     doAssert b.toBin(8) == "00000001"
     doAssert b.toBin(9) == "100000001"
   var
-    mask: BiggestInt = 1
-    shift: BiggestInt = 0
+    mask = BiggestUInt 1
+    shift = BiggestUInt 0
   assert(len > 0)
   result = newString(len)
   for j in countdown(len-1, 0):
-    result[j] = chr(int((x and mask) shr shift) + ord('0'))
-    shift = shift + 1
-    mask = mask shl 1
+    result[j] = chr(int((BiggestUInt(x) and mask) shr shift) + ord('0'))
+    inc shift
+    mask = mask shl BiggestUInt(1)
 
 proc toOct*(x: BiggestInt, len: Positive): string {.noSideEffect,
   rtl, extern: "nsuToOct".} =
@@ -917,14 +917,14 @@ proc toOct*(x: BiggestInt, len: Positive): string {.noSideEffect,
     doAssert b.toOct(3) == "001"
     doAssert b.toOct(5) == "01001"
   var
-    mask: BiggestInt = 7
-    shift: BiggestInt = 0
+    mask = BiggestUInt 7
+    shift = BiggestUInt 0
   assert(len > 0)
   result = newString(len)
   for j in countdown(len-1, 0):
-    result[j] = chr(int((x and mask) shr shift) + ord('0'))
-    shift = shift + 3
-    mask = mask shl 3
+    result[j] = chr(int((BiggestUInt(x) and mask) shr shift) + ord('0'))
+    inc shift, 3
+    mask = mask shl BiggestUInt(3)
 
 proc toHex*(x: BiggestInt, len: Positive): string {.noSideEffect,
   rtl, extern: "nsuToHex".} =
diff --git a/tests/stdlib/tstrutil.nim b/tests/stdlib/tstrutil.nim
index fffa85bd1a..f830205047 100644
--- a/tests/stdlib/tstrutil.nim
+++ b/tests/stdlib/tstrutil.nim
@@ -308,6 +308,13 @@ assert(' '.repeat(0) == "")
 assert(" ".repeat(0) == "")
 assert(spaces(0) == "")
 
+# bug #11369
+
+var num: int64 = -1
+assert num.toBin(64) == "1111111111111111111111111111111111111111111111111111111111111111"
+assert num.toOct(24) == "001777777777777777777777"
+
+
 # bug #8911
 when true:
   static: