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([$0], [AC_LINK_IFELSE]) 26 27m4_define([_AC_COMPILER_EXEEXT], 28[AC_LANG_CONFTEST([AC_LANG_PROGRAM( 29 [#include <stdio.h>], 30 [printf ("hello world\n");])]) 31# FIXME: Cleanup? 32AS_IF([AC_TRY_EVAL(ac_link)], [gcc_no_link=no], [gcc_no_link=yes]) 33if test x$gcc_no_link = xyes; then 34 # Setting cross_compile will disable run tests; it will 35 # also disable AC_CHECK_FILE but that's generally 36 # correct if we can't link. 37 cross_compiling=yes 38 EXEEXT= 39else 40 ]m4_defn([_AC_COMPILER_EXEEXT])dnl 41fi 42) 43 44m4_define([AC_LINK_IFELSE], 45if test x$gcc_no_link = xyes; then 46 AC_MSG_ERROR([Link tests are not allowed after [[$0]].]) 47fi 48m4_defn([AC_LINK_IFELSE])) 49 50dnl This is a shame. We have to provide a default for some link tests, 51dnl similar to the default for run tests. 52m4_define([AC_FUNC_MMAP], 53if test x$gcc_no_link = xyes; then 54 if test "x${ac_cv_func_mmap_fixed_mapped+set}" != xset; then 55 ac_cv_func_mmap_fixed_mapped=no 56 fi 57fi 58if test "x${ac_cv_func_mmap_fixed_mapped}" != xno; then 59 m4_defn([AC_FUNC_MMAP]) 60fi) 61 62m4_divert_pop()dnl 63])# GCC_NO_EXECUTABLES 64 65# Use the strongest available test out of AC_TRY_COMPILE and AC_TRY_LINK. 66AC_DEFUN([GCC_TRY_COMPILE_OR_LINK], 67[if test x$gcc_no_link = xyes; then 68 AC_TRY_COMPILE([$1], [$2], [$3], [$4]) 69else 70 AC_TRY_LINK([$1], [$2], [$3], [$4]) 71fi]) 72