From 581bcfe29094f525d2ab4e27455bed18a3eac811 Mon Sep 17 00:00:00 2001
From: flywind <43030857+xflywind@users.noreply.github.com>
Date: Wed, 18 Nov 2020 15:56:31 +0800
Subject: [PATCH] fix #6497 (#16027)

* fix #6497

* add testcase for #16027
---
 compiler/ast.nim         |  1 +
 tests/ccgbugs/t16027.nim | 13 +++++++++++++
 2 files changed, 14 insertions(+)
 create mode 100644 tests/ccgbugs/t16027.nim

diff --git a/compiler/ast.nim b/compiler/ast.nim
index 3d14aba66f..c75a149c02 100644
--- a/compiler/ast.nim
+++ b/compiler/ast.nim
@@ -1441,6 +1441,7 @@ proc copySym*(s: PSym; id: ItemId): PSym =
   result.position = s.position
   result.loc = s.loc
   result.annex = s.annex      # BUGFIX
+  result.constraint = s.constraint
   if result.kind in {skVar, skLet, skField}:
     result.guard = s.guard
     result.bitsize = s.bitsize
diff --git a/tests/ccgbugs/t16027.nim b/tests/ccgbugs/t16027.nim
new file mode 100644
index 0000000000..58f15eb6e3
--- /dev/null
+++ b/tests/ccgbugs/t16027.nim
@@ -0,0 +1,13 @@
+discard """
+  ccodecheck: "__restrict__"
+  action: compile
+  joinable: false
+"""
+
+# see bug #16027
+iterator myitems(s: seq[int]): int =
+  var data {.codegenDecl: "$# __restrict__ $#".} : ptr int = nil
+  yield 1
+
+for i in @[1].myitems:
+  discard