From 4948cf3b4c6690c28ca46ba97b0cf1de178bd894 Mon Sep 17 00:00:00 2001
From: Andreas Rumpf <rumpf_a@web.de>
Date: Mon, 30 Apr 2018 11:54:26 +0200
Subject: [PATCH 1/3] make the build more robust

---
 compiler/ccgexprs.nim | 11 ++++++++---
 compiler/condsyms.nim |  1 +
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/compiler/ccgexprs.nim b/compiler/ccgexprs.nim
index eb67db2b3..a3a85a3dc 100644
--- a/compiler/ccgexprs.nim
+++ b/compiler/ccgexprs.nim
@@ -909,9 +909,14 @@ proc genSeqElem(p: BProc, n, x, y: PNode, d: var TLoc) =
   if ty.kind in {tyRef, tyPtr}:
     ty = skipTypes(ty.lastSon, abstractVarRange) # emit range check:
   if optBoundsCheck in p.options:
-    linefmt(p, cpsStmts,
-          "if (!$2 || (NU)($1) >= (NU)($2->$3)) #raiseIndexError();$n",
-          rdLoc(b), rdLoc(a), lenField(p))
+    if ty.kind == tyString and not defined(nimNoZeroTerminator):
+      linefmt(p, cpsStmts,
+              "if (!$2 || (NU)($1) > (NU)($2->$3)) #raiseIndexError();$n",
+              rdLoc(b), rdLoc(a), lenField(p))
+    else:
+      linefmt(p, cpsStmts,
+              "if (!$2 || (NU)($1) >= (NU)($2->$3)) #raiseIndexError();$n",
+              rdLoc(b), rdLoc(a), lenField(p))
   if d.k == locNone: d.storage = OnHeap
   if skipTypes(a.t, abstractVar).kind in {tyRef, tyPtr}:
     a.r = rfmt(nil, "(*$1)", a.r)
diff --git a/compiler/condsyms.nim b/compiler/condsyms.nim
index 08dda9b6a..b1d0ccc7a 100644
--- a/compiler/condsyms.nim
+++ b/compiler/condsyms.nim
@@ -115,3 +115,4 @@ proc initDefines*() =
   defineSymbol("nimSymKind")
   defineSymbol("nimVmEqIdent")
   defineSymbol("nimNoNil")
+  defineSymbol("nimNoZeroTerminator")

From 50e1a489c04aaf204b1ead53a0013e1e96145844 Mon Sep 17 00:00:00 2001
From: Andreas Rumpf <rumpf_a@web.de>
Date: Mon, 30 Apr 2018 12:06:59 +0200
Subject: [PATCH 2/3] commands.nim: use let instead of var

---
 compiler/commands.nim | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/compiler/commands.nim b/compiler/commands.nim
index 06b487cf0..9f265fd15 100644
--- a/compiler/commands.nim
+++ b/compiler/commands.nim
@@ -188,11 +188,11 @@ proc processSpecificNote*(arg: string, state: TSpecialWord, pass: TCmdLinePass,
   if i < len(arg) and (arg[i] in {':', '='}): inc(i)
   else: invalidCmdLineOption(pass, orig, info)
   if state == wHint:
-    var x = findStr(msgs.HintsToStr, id)
+    let x = findStr(msgs.HintsToStr, id)
     if x >= 0: n = TNoteKind(x + ord(hintMin))
     else: localError(info, "unknown hint: " & id)
   else:
-    var x = findStr(msgs.WarningsToStr, id)
+    let x = findStr(msgs.WarningsToStr, id)
     if x >= 0: n = TNoteKind(x + ord(warnMin))
     else: localError(info, "unknown warning: " & id)
   case substr(arg, i).normalize

From 6dbfdecd74de1d8a4b53a095af85169951454a89 Mon Sep 17 00:00:00 2001
From: Andreas Rumpf <rumpf_a@web.de>
Date: Mon, 30 Apr 2018 12:07:12 +0200
Subject: [PATCH 3/3] make msgs.nim more robust

---
 compiler/msgs.nim | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/compiler/msgs.nim b/compiler/msgs.nim
index 5ae2c4970..838735753 100644
--- a/compiler/msgs.nim
+++ b/compiler/msgs.nim
@@ -474,6 +474,10 @@ const
   hintMin* = hintSuccess
   hintMax* = high(TMsgKind)
 
+static:
+  doAssert HintsToStr.len == ord(hintMax) - ord(hintMin) + 1
+  doAssert WarningsToStr.len == ord(warnMax) - ord(warnMin) + 1
+
 type
   TNoteKind* = range[warnMin..hintMax] # "notes" are warnings or hints
   TNoteKinds* = set[TNoteKind]