revert new scope for 'if'

compiler/ccgstmts.nim

@@ -232,13 +232,14 @@ proc genIfStmt(p: BProc, n: PNode) =
   for i in countup(0, sonsLen(n) - 1): 
     var it = n.sons[i]
     if it.len == 2: 
-      startBlock(p)
+      when newScopeForIf: startBlock(p)
       initLocExpr(p, it.sons[0], a)
       Lelse = getLabel(p)
       inc(p.labels)
       lineFF(p, cpsStmts, "if (!$1) goto $2;$n",
             "br i1 $1, label %LOC$3, label %$2$n" & "LOC$3: $n",
             [rdLoc(a), Lelse, toRope(p.labels)])
+      when not newScopeForIf: startBlock(p)
       genStmts(p, it.sons[1])
       endBlock(p)
       if sonsLen(n) > 1: 

compiler/options.nim

@@ -7,13 +7,14 @@
 #    distribution, for details about the copyright.
 #
 
-import 
+import
   os, lists, strutils, strtabs
   
 const
   hasTinyCBackend* = defined(tinyc)
   useEffectSystem* = true
   hasFFI* = defined(useFFI)
+  newScopeForIf* = false      # XXX activate for 0.9.4
 
 type                          # please make sure we have under 32 options
                               # (improves code efficiency a lot!)

compiler/sem.nim

@@ -100,7 +100,7 @@ proc newSymS(kind: TSymKind, n: PNode, c: PContext): PSym =
 
 proc newSymG*(kind: TSymKind, n: PNode, c: PContext): PSym =
   # like newSymS, but considers gensym'ed symbols
-  if n.kind == nkSym: 
+  if n.kind == nkSym:
     result = n.sym
     InternalAssert sfGenSym in result.flags
     InternalAssert result.kind == kind

compiler/semexprs.nim

@@ -1504,8 +1504,9 @@ proc semIf(c: PContext, n: PNode): PNode =
   for i in countup(0, sonsLen(n) - 1): 
     var it = n.sons[i]
     if it.len == 2:
-      openScope(c.tab)
+      when newScopeForIf: openScope(c.tab)
       it.sons[0] = forceBool(c, semExprWithType(c, it.sons[0]))
+      when not newScopeForIf: openScope(c.tab)
       it.sons[1] = semExprBranch(c, it.sons[1])
       typ = commonType(typ, it.sons[1].typ)
       closeScope(c.tab)