4 files changed, 14 insertions, 2 deletions
diff --git a/compiler/renderer.nim b/compiler/renderer.nim
index ce818e3cd..ffdb60696 100644
--- a/compiler/renderer.nim
+++ b/compiler/renderer.nim
@@ -503,6 +503,7 @@ proc gsub(g: var TSrcGen, n: PNode) =
 
 proc hasCom(n: PNode): bool =
   result = false
+  if n.isNil: return false
   if n.comment != nil: return true
   case n.kind
   of nkEmpty..nkNilLit: discard
diff --git a/compiler/seminst.nim b/compiler/seminst.nim
index dc36ecf34..f72e2dc5b 100644
--- a/compiler/seminst.nim
+++ b/compiler/seminst.nim
@@ -176,7 +176,9 @@ proc instantiateProcType(c: PContext, pt: TIdTable,
 
   for i in 1 .. <result.len:
     # twrong_field_caching requires these 'resetIdTable' calls:
-    if i > 1: resetIdTable(cl.symMap)
+    if i > 1:
+      resetIdTable(cl.symMap)
+      resetIdTable(cl.localCache)
     result.sons[i] = replaceTypeVarsT(cl, result.sons[i])
     propagateToOwner(result, result.sons[i])
     internalAssert originalParams[i].kind == nkSym
@@ -196,6 +198,7 @@ proc instantiateProcType(c: PContext, pt: TIdTable,
       addDecl(c, result.n.sons[i].sym)
 
   resetIdTable(cl.symMap)
+  resetIdTable(cl.localCache)
   result.sons[0] = replaceTypeVarsT(cl, result.sons[0])
   result.n.sons[0] = originalParams[0].copyTree
 
diff --git a/compiler/sempass2.nim b/compiler/sempass2.nim
index 6928dbaf4..5a243afa0 100644
--- a/compiler/sempass2.nim
+++ b/compiler/sempass2.nim
@@ -764,7 +764,7 @@ proc track(tracked: PEffects, n: PNode) =
     setLen(tracked.locked, oldLocked)
     tracked.currLockLevel = oldLockLevel
   of nkTypeSection, nkProcDef, nkConverterDef, nkMethodDef, nkIteratorDef,
-      nkMacroDef, nkTemplateDef:
+      nkMacroDef, nkTemplateDef, nkLambda, nkDo:
     discard
   else:
     for i in 0 .. <safeLen(n): track(tracked, n.sons[i])
diff --git a/compiler/semtypinst.nim b/compiler/semtypinst.nim
index cbd7999c7..914b92fc8 100644
--- a/compiler/semtypinst.nim
+++ b/compiler/semtypinst.nim
@@ -418,15 +418,23 @@ proc replaceTypeVarsTAux(cl: var TReplTypeVars, t: PType): PType =
     result = t
 
   of tyGenericInst:
+    result = PType(idTableGet(cl.localCache, t))
+    if result != nil: return result
     result = instCopyType(cl, t)
+    idTablePut(cl.localCache, t, result)
     for i in 1 .. <result.sonsLen:
       result.sons[i] = replaceTypeVarsT(cl, result.sons[i])
     propagateToOwner(result, result.lastSon)
 
   else:
     if containsGenericType(t):
+      #if not cl.allowMetaTypes:
+      result = PType(idTableGet(cl.localCache, t))
+      if result != nil: return result
       result = instCopyType(cl, t)
       result.size = -1 # needs to be recomputed
+      #if not cl.allowMetaTypes:
+      idTablePut(cl.localCache, t, result)
 
       for i in countup(0, sonsLen(result) - 1):
         if result.sons[i] != nil: