diff --git a/e_os2.h b/e_os2.h
index 18b68527a..ea92ff578 100644
--- a/e_os2.h
+++ b/e_os2.h
@@ -144,7 +144,7 @@ extern "C" {
 
 /* --------------------------------- Unix ---------------------------------- */
 #ifdef OPENSSL_SYS_UNIX
-# if defined(linux) || defined(OPENSSL_SYSNAME_LINUX)
+# if defined(linux) || defined(__linux__) || defined(OPENSSL_SYSNAME_LINUX)
 #  define OPENSSL_SYS_LINUX
 # endif
 # ifdef OPENSSL_SYSNAME_MPE