2 dnl Copyright (C) 2006-2020 Free Software Foundation, Inc.
3 dnl This file is free software; the Free Software Foundation
4 dnl gives unlimited permission to copy and/or distribute it,
5 dnl with or without modifications, as long as this notice is preserved.
7 AC_DEFUN([gl_FUNC_TSEARCH],
9 AC_REQUIRE([gl_SEARCH_H_DEFAULTS])
10 AC_CHECK_FUNCS([tsearch twalk])
11 if test $ac_cv_func_tsearch = yes; then
12 dnl On OpenBSD 4.0, the return value of tdelete() is incorrect.
13 AC_REQUIRE([AC_PROG_CC])
14 AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
15 AC_CACHE_CHECK([whether tdelete works], [gl_cv_func_tdelete_works],
17 AC_RUN_IFELSE([AC_LANG_SOURCE([[
21 cmp_fn (const void *a, const void *b)
23 return *(const int *) a - *(const int *) b;
31 if (!(tfind (&x, &root, cmp_fn) == NULL))
33 tsearch (&x, &root, cmp_fn);
34 if (!(tfind (&x, &root, cmp_fn) != NULL))
36 if (!(tdelete (&x, &root, cmp_fn) != NULL))
39 }]])], [gl_cv_func_tdelete_works=yes], [gl_cv_func_tdelete_works=no],
41 openbsd*) gl_cv_func_tdelete_works="guessing no" ;;
42 # Guess yes on native Windows.
43 mingw*) gl_cv_func_tdelete_works="guessing yes" ;;
44 *) gl_cv_func_tdelete_works="guessing yes" ;;
48 case "$gl_cv_func_tdelete_works" in
56 if test $ac_cv_func_twalk != yes; then
61 # Prerequisites of lib/tsearch.c.
62 AC_DEFUN([gl_PREREQ_TSEARCH], [