link: detect FreeBSD bug

[gnulib.git] / m4 / link.m4

diff --git a/m4/link.m4 b/m4/link.m4
index a212ee2..d5fcef9 100644 (file)
--- a/m4/link.m4
+++ b/m4/link.m4
@@ -1,4 +1,4 @@
-# link.m4 serial 3
+# link.m4 serial 4
 dnl Copyright (C) 2009 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -15,13 +15,21 @@ AC_DEFUN([gl_FUNC_LINK],
     AC_CACHE_CHECK([whether link handles trailing slash correctly],
       [gl_cv_func_link_works],
       [touch conftest.a
+       # Assume that if we have lstat, we can also check symlinks.
+       if test $ac_cv_func_lstat = yes; then
+         ln -s conftest.a conftest.lnk
+       fi
        AC_RUN_IFELSE(
          [AC_LANG_PROGRAM(
            [[#include <unistd.h>
-]], [[return !link ("conftest.a", "conftest.b/");]])],
+]], [[if (!link ("conftest.a", "conftest.b/")) return 1;
+#if HAVE_LSTAT
+      if (!link ("conftest.lnk/", "conftest.b")) return 2;
+#endif
+           ]])],
          [gl_cv_func_link_works=yes], [gl_cv_func_link_works=no],
          [gl_cv_func_link_works="guessing no"])
-       rm -f conftest.a conftest.b])
+       rm -f conftest.a conftest.b conftest.lnk])
     if test "$gl_cv_func_link_works" != yes; then
       REPLACE_LINK=1
       AC_LIBOBJ([link])