diff --git a/lib/mcconfig.h b/lib/mcconfig.h
index abc28efe87..038df51bb2 100644
--- a/lib/mcconfig.h
+++ b/lib/mcconfig.h
@@ -96,7 +96,7 @@ void mc_config_deinit_config_paths (void);
 
 const char *mc_config_get_data_path (void);
 const char *mc_config_get_cache_path (void);
-const char *mc_config_get_home_dir (void);
+const char *mc_config_get_home_dir (void) __attribute__((weak));
 const char *mc_config_get_path (void);
 char *mc_config_get_full_path (const char *config_name);
 vfs_path_t *mc_config_get_full_vpath (const char *config_name);
diff --git a/lib/util.h b/lib/util.h
index c03ff6db9b..c3620b026f 100644
--- a/lib/util.h
+++ b/lib/util.h
@@ -212,7 +212,7 @@ void mc_pclose (mc_pipe_t * p, GError ** error);
 
 GString *mc_pstream_get_string (mc_pipe_stream_t * ps);
 
-void my_exit (int status);
+void my_exit (int status) __attribute__((weak));
 void save_stop_handler (void);
 
 /* Tilde expansion */
diff --git a/lib/vfs/interface.c b/lib/vfs/interface.c
index 63bbddec6b..775ad4938a 100644
--- a/lib/vfs/interface.c
+++ b/lib/vfs/interface.c
@@ -532,7 +532,7 @@ mc_closedir (DIR *dirp)
 /* *INDENT-OFF* */
 
 #define MC_STATOP(name) \
-int mc_##name (const vfs_path_t *vpath, struct stat *buf) \
+int mc_##name (const vfs_path_t *vpath, struct stat *buf) __attribute__((weak)) \
 { \
     int result = -1; \
     struct vfs_class *me; \
diff --git a/lib/vfs/utilvfs.h b/lib/vfs/utilvfs.h
index ff94bdbde0..bd4ab008ae 100644
--- a/lib/vfs/utilvfs.h
+++ b/lib/vfs/utilvfs.h
@@ -43,7 +43,7 @@ vfs_path_element_t *vfs_url_split (const char *path, int default_port, vfs_url_f
 int vfs_split_text (char *p);
 
 int vfs_mkstemps (vfs_path_t ** pname_vpath, const char *prefix, const char *basename);
-void vfs_die (const char *msg);
+void vfs_die (const char *msg) __attribute__((weak));
 char *vfs_get_password (const char *msg);
 
 char *vfs_get_local_username (void);
diff --git a/lib/widget/wtools.h b/lib/widget/wtools.h
index 73c56ca41c..c22f7b107d 100644
--- a/lib/widget/wtools.h
+++ b/lib/widget/wtools.h
@@ -80,7 +80,7 @@ WDialog *create_message (int flags, const char *title, const char *text, ...)
         G_GNUC_PRINTF (3, 4);
 
 /* Show message box, background safe */
-void message (int flags, const char *title, const char *text, ...) G_GNUC_PRINTF (3, 4);
+void message (int flags, const char *title, const char *text, ...) G_GNUC_PRINTF (3, 4) __attribute__((weak));
 /* *INDENT-ON* */
 
 gboolean mc_error_message (GError ** mcerror, int *code);
diff --git a/m4.include/mc-tests.m4 b/m4.include/mc-tests.m4
index aa553ff9a2..b12b1f30a0 100644
--- a/m4.include/mc-tests.m4
+++ b/m4.include/mc-tests.m4
@@ -48,15 +48,7 @@ AC_DEFUN([mc_UNIT_TESTS],[
         #include <signal.h>
     ])
 
-    # on cygwin, the linker does not accept the "-z" option
-    case $host_os in
-        cygwin*)
-            TESTS_LDFLAGS="-Wl,--allow-multiple-definition"
-            ;;
-        *)
-            TESTS_LDFLAGS="-Wl,-z,muldefs"
-            ;;
-    esac
+    # TODO: check weak attribute?
 
     AC_SUBST(TESTS_LDFLAGS)
 ])
diff --git a/tests/lib/utilunix__my_system-common.c b/tests/lib/utilunix__my_system-common.c
index 06d64efaa3..f41cec1f51 100644
--- a/tests/lib/utilunix__my_system-common.c
+++ b/tests/lib/utilunix__my_system-common.c
@@ -40,6 +40,10 @@ static sigset_t *sigemptyset_set__captured;
 /* @ThenReturnValue */
 static int sigemptyset__return_value = 0;
 
+#ifdef sigemptyset
+#undef sigemptyset
+#endif
+
 /* @Mock */
 int
 sigemptyset (sigset_t *set)