sempass2: bugfixes

compiler/guards.nim

@@ -123,7 +123,7 @@ proc neg(n: PNode): PNode =
         let eAsNode = newIntNode(nkIntLit, e.sym.position)
         if not inSet(n.sons[1], eAsNode): s.add eAsNode
       result.sons[1] = s
-    elif lengthOrd(t) < 1000:
+    elif t.kind notin {tyString, tySequence} and lengthOrd(t) < 1000:
       result.sons[1] = complement(n.sons[1])
     else:
       # not ({2, 3, 4}.contains(x))   x != 2 and x != 3 and x != 4
@@ -908,5 +908,5 @@ proc buildProperFieldCheck(access, check: PNode): PNode =
 proc checkFieldAccess*(m: TModel, n: PNode) =
   for i in 1..n.len-1:
     let check = buildProperFieldCheck(n.sons[0], n.sons[i])
-    if m.doesImply(check) != impYes:
+    if check != nil and m.doesImply(check) != impYes:
       message(n.info, warnProveField, renderTree(n.sons[0])); break

compiler/sempass2.nim

@@ -560,7 +560,10 @@ proc trackCase(tracked: PEffects, n: PNode) =
   track(tracked, n.sons[0])
   let oldState = tracked.init.len
   let oldFacts = tracked.guards.len
-  let interesting = interestingCaseExpr(n.sons[0]) and warnProveField in gNotes
+  let stringCase = skipTypes(n.sons[0].typ,
+        abstractVarRange-{tyTypeDesc}).kind in {tyFloat..tyFloat128, tyString}
+  let interesting = not stringCase and interestingCaseExpr(n.sons[0]) and
+        warnProveField in gNotes
   var inter: TIntersection = @[]
   var toCover = 0
   for i in 1.. <n.len:
@@ -575,13 +578,8 @@ proc trackCase(tracked: PEffects, n: PNode) =
     for i in oldState.. <tracked.init.len:
       addToIntersection(inter, tracked.init[i])
 
-  let exh = case skipTypes(n.sons[0].typ, abstractVarRange-{tyTypeDesc}).kind
-            of tyFloat..tyFloat128, tyString:
-              lastSon(n).kind == nkElse
-            else:
-              true
   setLen(tracked.init, oldState)
-  if exh:
+  if not stringCase or lastSon(n).kind == nkElse:
     for id, count in items(inter):
       if count >= toCover: tracked.init.add id
     # else we can't merge