diff --git a/library/common.h b/library/common.h
index ae6625b..46af79f 100644
--- a/library/common.h
+++ b/library/common.h
@@ -142,4 +142,11 @@
 #define /*no-check-names*/ __func__ __FUNCTION__
 #endif
 
+/* Define `asm` for compilers which don't define it. */
+/* *INDENT-OFF* */
+#ifndef asm
+#define asm __asm__
+#endif
+/* *INDENT-ON* */
+
 #endif /* MBEDTLS_LIBRARY_COMMON_H */