diff --git a/compiler/ast.nim b/compiler/ast.nim
index 0e4700065d..65806ea1f2 100755
--- a/compiler/ast.nim
+++ b/compiler/ast.nim
@@ -675,7 +675,6 @@ type
     size*: BiggestInt         # the size of the type in bytes
                               # -1 means that the size is unkwown
     align*: int               # the type's alignment requirements
-    containerID*: int         # used for type checking of generics
     loc*: TLoc
 
   TPair*{.final.} = object 
@@ -1012,7 +1011,6 @@ proc assignType(dest, src: PType) =
   dest.n = src.n
   dest.size = src.size
   dest.align = src.align
-  dest.containerID = src.containerID
   dest.destructor = src.destructor
   # this fixes 'type TLock = TSysLock':
   if src.sym != nil:
diff --git a/compiler/rodread.nim b/compiler/rodread.nim
index 5dccee9a71..a4287f8e8c 100755
--- a/compiler/rodread.nim
+++ b/compiler/rodread.nim
@@ -327,9 +327,6 @@ proc decodeType(r: PRodReader, info: TLineInfo): PType =
     result.align = decodeVInt(r.s, r.pos)
   else: 
     result.align = 2
-  if r.s[r.pos] == '@': 
-    inc(r.pos)
-    result.containerID = decodeVInt(r.s, r.pos)
   decodeLoc(r, result.loc, info)
   while r.s[r.pos] == '^': 
     inc(r.pos)
diff --git a/compiler/rodwrite.nim b/compiler/rodwrite.nim
index c0a0cc4eb7..9eab844d19 100755
--- a/compiler/rodwrite.nim
+++ b/compiler/rodwrite.nim
@@ -230,9 +230,6 @@ proc encodeType(w: PRodWriter, t: PType, result: var string) =
   if t.align != 2: 
     add(result, '=')
     encodeVInt(t.align, result)
-  if t.containerID != 0: 
-    add(result, '@')
-    encodeVInt(t.containerID, result)
   encodeLoc(w, t.loc, result)
   for i in countup(0, sonsLen(t) - 1): 
     if t.sons[i] == nil: 
diff --git a/compiler/semstmts.nim b/compiler/semstmts.nim
index c38e2f3ad6..9867c20bec 100755
--- a/compiler/semstmts.nim
+++ b/compiler/semstmts.nim
@@ -532,9 +532,6 @@ proc typeSectionRightSidePass(c: PContext, n: PNode) =
       openScope(c.tab)
       pushOwner(s)
       if s.magic == mNone: s.typ.kind = tyGenericBody
-      if s.typ.containerID != 0: 
-        InternalError(a.info, "semTypeSection: containerID")
-      s.typ.containerID = s.typ.id
       # XXX for generic type aliases this is not correct! We need the
       # underlying Id really: 
       #
diff --git a/compiler/semtypes.nim b/compiler/semtypes.nim
index bda0047cab..db2ef1b3f0 100755
--- a/compiler/semtypes.nim
+++ b/compiler/semtypes.nim
@@ -769,9 +769,6 @@ proc semGeneric(c: PContext, n: PNode, s: PSym, prev: PType): PType =
     return newOrPrevType(tyError, prev, c)
   elif s.typ.kind != tyGenericBody:
     isConcrete = false
-  elif s.typ.containerID == 0: 
-    InternalError(n.info, "semtypes.semGeneric")
-    return newOrPrevType(tyError, prev, c)
   elif sonsLen(n) != sonsLen(s.typ): 
     LocalError(n.info, errWrongNumberOfArguments)
     return newOrPrevType(tyError, prev, c)
diff --git a/compiler/sigmatch.nim b/compiler/sigmatch.nim
index 953dcfa747..72a5762a95 100755
--- a/compiler/sigmatch.nim
+++ b/compiler/sigmatch.nim
@@ -493,11 +493,10 @@ proc typeRel(c: var TCandidate, f, a: PType): TTypeRelation =
       # simply no match for now:
       nil
     elif x.kind == tyGenericInst and 
-          (f.sons[0].containerID == x.sons[0].containerID) and
-          (sonsLen(x) - 1 == sonsLen(f)): 
-      assert(x.sons[0].kind == tyGenericBody)
-      for i in countup(1, sonsLen(f) - 1): 
-        if x.sons[i].kind == tyGenericParam: 
+          (f.sons[0] == x.sons[0]) and
+          (sonsLen(x) - 1 == sonsLen(f)):
+      for i in countup(1, sonsLen(f) - 1):
+        if x.sons[i].kind == tyGenericParam:
           InternalError("wrong instantiated type!")
         elif typeRel(c, f.sons[i], x.sons[i]) <= isSubtype: return 
       result = isGeneric