1 files changed, 19 insertions, 0 deletions
diff --git a/tests/openarray/tuncheckedarray.nim b/tests/openarray/tuncheckedarray.nim
new file mode 100644
index 000000000..c8ca9d2d4
--- /dev/null
+++ b/tests/openarray/tuncheckedarray.nim
@@ -0,0 +1,19 @@
+discard """
+  exitcode: 0
+  targets: "c cpp"
+"""
+
+proc main =
+  block: # issue 19171
+    var a = ['A']
+    proc mutB(x: var openArray[char]) =
+      x[0] = 'B'
+    mutB(toOpenArray(cast[ptr UncheckedArray[char]](addr a), 0, 0))
+    doAssert a[0] == 'B'
+    proc mutC(x: var openArray[char]; c: char) =
+      x[0] = c
+    let p = cast[ptr UncheckedArray[char]](addr a)
+    mutC(toOpenArray(p, 0, 0), 'C')
+    doAssert p[0] == 'C'
+
+main()