3 files changed, 41 insertions, 0 deletions
diff --git a/tests/objects/t3734.nim b/tests/objects/t3734.nim
new file mode 100644
index 000000000..cebef6081
--- /dev/null
+++ b/tests/objects/t3734.nim
@@ -0,0 +1,17 @@
+discard """
+output: "i0"
+"""
+
+type
+  Application = object
+      config: void
+      i: int
+      f: void
+
+proc printFields(rec: Application) =
+  for k, v in fieldPairs(rec):
+    echo k, v
+
+var app: Application
+
+printFields(app)
diff --git a/tests/objects/tobjcov.nim b/tests/objects/tobjcov.nim
index 817c1fcda..6c587e04d 100644
--- a/tests/objects/tobjcov.nim
+++ b/tests/objects/tobjcov.nim
@@ -1,8 +1,12 @@
 discard """
 action: compile
+target: "c"
 """
 
 # Covariance is not type safe:
+# Note: `nim cpp` makes it a compile error (after codegen), even with:
+# `var f = cast[proc (x: var TA) {.nimcall.}](cast[pointer](bp))`, which
+# currently removes all the `cast` in cgen'd code, hence the compile error.
 
 type
   TA = object of RootObj
diff --git a/tests/objects/tobject.nim b/tests/objects/tobject.nim
index 61ef7442e..fbf531c3d 100644
--- a/tests/objects/tobject.nim
+++ b/tests/objects/tobject.nim
@@ -17,3 +17,23 @@ suite "object basic methods":
     check($obj == "(foo: 1)")
   test "it should test equality based on fields":
     check(makeObj(1) == makeObj(1))
+
+# bug #10203
+
+type
+  TMyObj = TYourObj
+  TYourObj = object of RootObj
+    x, y: int
+
+proc init: TYourObj =
+  result.x = 0
+  result.y = -1
+
+proc f(x: var TYourObj) =
+  discard
+
+var m: TMyObj = init()
+f(m)
+
+var a: TYourObj = m
+var b: TMyObj = a