diff --git a/ports/unix/variants/coverage/frzmpy/frzmpy3.py b/ports/unix/variants/coverage/frzmpy/frzmpy3.py
new file mode 100644
index 0000000000..617fac5523
--- /dev/null
+++ b/ports/unix/variants/coverage/frzmpy/frzmpy3.py
@@ -0,0 +1,6 @@
+# Test freezing objects that may not be handled well by the build process.
+
+print("\\")
+print("\nX")
+print(repr("\x1b"))
+print(b"\x00\xff")
diff --git a/tests/unix/extra_coverage.py b/tests/unix/extra_coverage.py
index 8ea27cbf2f..bb22485026 100644
--- a/tests/unix/extra_coverage.py
+++ b/tests/unix/extra_coverage.py
@@ -89,6 +89,9 @@ try:
 except ZeroDivisionError:
     print("ZeroDivisionError")
 
+# test importing various objects
+import frzmpy3
+
 # test for MP_QSTR_NULL regression
 from frzqstr import returns_NULL
 
diff --git a/tests/unix/extra_coverage.py.exp b/tests/unix/extra_coverage.py.exp
index 8ee233a712..1a5a2cde85 100644
--- a/tests/unix/extra_coverage.py.exp
+++ b/tests/unix/extra_coverage.py.exp
@@ -174,4 +174,9 @@ frzstr_pkg2.mod
 frzmpy_pkg2.mod
 1
 ZeroDivisionError
+\
+
+X
+'\x1b'
+b'\x00\xff'
 NULL