diff --git a/backend.native/tests/interop/basics/cstdio.def b/backend.native/tests/interop/basics/cstdio.def
index e2f7b2d512e..13dc2a82526 100644
--- a/backend.native/tests/interop/basics/cstdio.def
+++ b/backend.native/tests/interop/basics/cstdio.def
@@ -1,4 +1,5 @@
 headers = stdio.h
+compilerOpts.osx = -D_ANSI_SOURCE
 
 ---
 
diff --git a/samples/socket/src/main/c_interop/sockets.def b/samples/socket/src/main/c_interop/sockets.def
index 9d9821313f6..f3daed92c32 100644
--- a/samples/socket/src/main/c_interop/sockets.def
+++ b/samples/socket/src/main/c_interop/sockets.def
@@ -1,6 +1,5 @@
 headers = sys/socket.h sys/errno.h netdb.h stdio.h string.h unistd.h stdlib.h netinet/in.h
-excludeDependentModules.osx = true
-
+compilerOpts.osx = -D_ANSI_SOURCE
 ---
 
 static int interop_errno() {