From 84ca1f3bf3d0095034973fae8c36999f8778c451 Mon Sep 17 00:00:00 2001
From: Araq <rumpf_a@web.de>
Date: Mon, 27 May 2019 22:38:06 +0200
Subject: [PATCH] hotfix for 32bit unsigned 'range' checking; incomplete,
 unknown why some operations produce range checks

---
 compiler/ccgexprs.nim | 3 ++-
 lib/system/chcks.nim  | 6 ++++++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/compiler/ccgexprs.nim b/compiler/ccgexprs.nim
index a4046635b..a1a9ffe41 100644
--- a/compiler/ccgexprs.nim
+++ b/compiler/ccgexprs.nim
@@ -1967,11 +1967,12 @@ proc genRangeChck(p: BProc, n: PNode, d: var TLoc, magic: string) =
     putIntoDest(p, d, n, "(($1) ($2))" %
         [getTypeDesc(p.module, dest), rdCharLoc(a)], a.storage)
   else:
+    let mm = if dest.kind in {tyUInt32, tyUInt64, tyUInt}: "chckRangeU" else: magic
     initLocExpr(p, n.sons[0], a)
     putIntoDest(p, d, lodeTyp dest, ropecg(p.module, "(($1)#$5($2, $3, $4))", [
         getTypeDesc(p.module, dest), rdCharLoc(a),
         genLiteral(p, n.sons[1], dest), genLiteral(p, n.sons[2], dest),
-        magic]), a.storage)
+        mm]), a.storage)
 
 proc genConv(p: BProc, e: PNode, d: var TLoc) =
   let destType = e.typ.skipTypes({tyVar, tyLent, tyGenericInst, tyAlias, tySink})
diff --git a/lib/system/chcks.nim b/lib/system/chcks.nim
index d108e09f1..303a8945a 100644
--- a/lib/system/chcks.nim
+++ b/lib/system/chcks.nim
@@ -46,6 +46,12 @@ proc chckRange64(i, a, b: int64): int64 {.compilerproc.} =
   else:
     raiseRangeError(i)
 
+proc chckRangeU(i, a, b: uint64): uint64 {.compilerproc.} =
+  if i >= a and i <= b:
+    return i
+  else:
+    sysFatal(RangeError, "value out of range")
+
 proc chckRangeF(x, a, b: float): float =
   if x >= a and x <= b:
     return x