diff --git a/lib/pure/concurrency/atomics.nim b/lib/pure/concurrency/atomics.nim
index 818f1b37acbaa..d0dcaa9749f8a 100644
--- a/lib/pure/concurrency/atomics.nim
+++ b/lib/pure/concurrency/atomics.nim
@@ -59,7 +59,7 @@ when (defined(cpp) and defined(nimUseCppAtomics)) or defined(nimdoc):
   {.push, header: "<atomic>".}
 
   type
-    MemoryOrder* {.importcpp: "std::memory_order".} = enum
+    MemoryOrder* {.importcpp: "std::memory_order", size: sizeof(cint).} = enum
       ## Specifies how non-atomic operations can be reordered around atomic
       ## operations.
 
@@ -286,7 +286,7 @@ else:
         x
 
     type
-      MemoryOrder* {.importc: "memory_order".maybeWrapStd.} = enum
+      MemoryOrder* {.importc: "memory_order".maybeWrapStd, size: sizeof(cint).} = enum
         moRelaxed
         moConsume
         moAcquire
diff --git a/tests/stdlib/concurrency/tatomics.nim b/tests/stdlib/concurrency/tatomics.nim
index 08f2e7d3eed7c..b8a1f359ac5c2 100644
--- a/tests/stdlib/concurrency/tatomics.nim
+++ b/tests/stdlib/concurrency/tatomics.nim
@@ -1,6 +1,6 @@
 discard """
   # test C with -d:nimUseCppAtomics as well to check nothing breaks
-  matrix: "--mm:refc; --mm:orc; --mm:refc -d:nimUseCppAtomics; --mm:orc -d:nimUseCppAtomics"
+  matrix: "--mm:refc; --mm:orc -d:checkabi; --mm:refc -d:nimUseCppAtomics; --mm:orc -d:nimUseCppAtomics"
   targets: "c cpp"
 """