diff --git a/include/mbedtls/dhm.h b/include/mbedtls/dhm.h
index 40916c6..f9725ab 100644
--- a/include/mbedtls/dhm.h
+++ b/include/mbedtls/dhm.h
@@ -296,10 +296,19 @@
 int mbedtls_dhm_parse_dhmfile( mbedtls_dhm_context *dhm, const char *path );
 #endif /* MBEDTLS_FS_IO */
 #endif /* MBEDTLS_ASN1_PARSE_C */
-#else
+
+#ifdef __cplusplus
+}
+#endif
+
+#else /* MBEDTLS_DHM_ALT */
 #include "dhm_alt.h"
 #endif /* MBEDTLS_DHM_ALT */
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 /**
  * \brief          Checkup routine
  *