fix crash with undeclared proc type pragma macro in generics

fixes nim-lang#24489

compiler/semtypes.nim

@@ -1867,7 +1867,7 @@ proc applyTypeSectionPragmas(c: PContext; pragmas, operand: PNode): PNode =
           x.add(operand.copyTreeWithoutNode(p))
           # recursion assures that this works for multiple macro annotations too:
           var r = semOverloadedCall(c, x, x, {skMacro, skTemplate}, {efNoUndeclared})
-          if r != nil:
+          if r != nil and (r.typ == nil or r.typ.kind != tyFromExpr):
             doAssert r[0].kind == nkSym
             let m = r[0].sym
             case m.kind

tests/pragmas/tundeclaredgenericmacro.nim

@@ -0,0 +1,32 @@
+import std/[asyncdispatch, httpclient, strutils, json, times]
+
+type
+  Tree[T] = object
+    x: T
+    rr: seq[Tree[T]]
+  I = Tree[int]
+  F = Tree[Future[string]]
+
+proc title(t: I): Future[string] {.async,gcsafe.} =
+  let cli = newAsyncHttpClient()
+  let c = await cli.getContent("https://jsonplaceholder.typicode.com/todos/" & $t.x)
+  c.parseJson()["title"].getStr()
+
+proc map[T,U](t: T, f: proc (x: T): U{.async.gcsafe.}): U = #[tt.Error
+                                            ^ invalid pragma: async.gcsafe]#
+  result.x = f(t)
+  for r in t.rr:
+    result.rr.add map(r, f)
+
+proc f(t: F, l: int) {.async.} =
+  echo repeat(' ', l), (await t.x)
+  for r in t.rr:
+    await f(r, l+1)
+
+proc asyncMain() {.async.} =
+  let t = I(x: 1, rr: @[I(x: 2), I(x: 3, rr: @[I(x: 4), I(x: 5)])])
+  await f(map[I,F](t, title), 0)
+
+let a = now()
+waitFor asyncMain()
+echo now() - a