1# GCC_NO_EXECUTABLES
2# -----------------
3# FIXME: The GCC team has specific needs which the current Autoconf
4# framework cannot solve elegantly.  This macro implements a dirty
5# hack until Autoconf is able to provide the services its users
6# need.
7#
8# Several of the support libraries that are often built with GCC can't
9# assume the tool-chain is already capable of linking a program: the
10# compiler often expects to be able to link with some of such
11# libraries.
12#
13# In several of these libraries, workarounds have been introduced to
14# avoid the AC_PROG_CC_WORKS test, that would just abort their
15# configuration.  The introduction of AC_EXEEXT, enabled either by
16# libtool or by CVS autoconf, have just made matters worse.
17#
18# Unlike the previous AC_NO_EXECUTABLES, this test does not
19# disable link tests at autoconf time, but at configure time.
20# This allows AC_NO_EXECUTABLES to be invoked conditionally.
21AC_DEFUN_ONCE([GCC_NO_EXECUTABLES],
22[m4_divert_push([KILL])
23
24AC_BEFORE([$0], [_AC_COMPILER_EXEEXT])
25AC_BEFORE([$0], [AC_LINK_IFELSE])
26
27m4_define([_AC_COMPILER_EXEEXT],
28AC_LANG_CONFTEST([AC_LANG_PROGRAM()])
29# FIXME: Cleanup?
30AS_IF([AC_TRY_EVAL(ac_link)], [gcc_no_link=no], [gcc_no_link=yes])
31if test x$gcc_no_link = xyes; then
32  # Setting cross_compile will disable run tests; it will
33  # also disable AC_CHECK_FILE but that's generally
34  # correct if we can't link.
35  cross_compiling=yes
36  EXEEXT=
37else
38  m4_defn([_AC_COMPILER_EXEEXT])dnl
39fi
40)
41
42m4_define([AC_LINK_IFELSE],
43if test x$gcc_no_link = xyes; then
44  AC_MSG_ERROR([Link tests are not allowed after [[$0]].])
45fi
46m4_defn([AC_LINK_IFELSE]))
47
48dnl This is a shame.  We have to provide a default for some link tests,
49dnl similar to the default for run tests.
50m4_define([AC_FUNC_MMAP],
51if test x$gcc_no_link = xyes; then
52  if test "x${ac_cv_func_mmap_fixed_mapped+set}" != xset; then
53    ac_cv_func_mmap_fixed_mapped=no
54  fi
55fi
56if test "x${ac_cv_func_mmap_fixed_mapped+set}" != xset; then
57  m4_defn([AC_FUNC_MMAP])
58fi)
59
60m4_divert_pop()dnl
61])# GCC_NO_EXECUTABLES
62