diff --git a/compiler/semexprs.nim b/compiler/semexprs.nim
index de2259eb4f..befcd7df12 100644
--- a/compiler/semexprs.nim
+++ b/compiler/semexprs.nim
@@ -646,6 +646,9 @@ proc semArrayConstr(c: PContext, n: PNode, flags: TExprFlags): PNode =
 proc fixAbstractType(c: PContext, n: PNode) =
   for i in 1..<n.len:
     let it = n[i]
+    if it == nil:
+      localError(c.config, n.info, "'$1' has nil child at index $2" % [renderTree(n, {renderNoComments}), $i])
+      return
     # do not get rid of nkHiddenSubConv for OpenArrays, the codegen needs it:
     if it.kind == nkHiddenSubConv and
         skipTypes(it.typ, abstractVar).kind notin {tyOpenArray, tyVarargs}:
diff --git a/tests/macros/t16758.nim b/tests/macros/t16758.nim
new file mode 100644
index 0000000000..66b6d42c56
--- /dev/null
+++ b/tests/macros/t16758.nim
@@ -0,0 +1,38 @@
+discard """
+errormsg: "'blk.p(a)' has nil child at index 1"
+action: reject
+"""
+import macros
+
+type BlockLiteral[T] = object
+  p: T
+
+proc p[T](a:int) = echo 1
+proc p[T](a:string) = echo "a"
+
+iterator arguments(formalParams: NimNode): NimNode =
+  var iParam = 0
+  for i in 1 ..< formalParams.len:
+    let pp = formalParams[i]
+    for j in 0 .. pp.len - 3:
+      yield pp[j]
+      inc iParam
+
+macro implementInvoke(T: typedesc): untyped =
+  let t = getTypeImpl(T)[1]
+
+  let call = newCall(newDotExpr(ident"blk", ident"p"))
+  let params = copyNimTree(t[0])
+  result = newProc(ident"invoke", body = call)
+  # result[2] = newTree(nnkGenericParams,T)
+  for n in arguments(params):
+    call.add(n)
+  
+  params.insert(1, newIdentDefs(ident"blk", newTree(nnkBracketExpr, bindSym"BlockLiteral", T)))
+  result.params = params
+
+proc getInvoke(T: typedesc) =
+  implementInvoke(T)
+
+
+getInvoke(proc(a: int))