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. 21 AC_DEFUN_ONCE([GCC_NO_EXECUTABLES], 22 [m4_divert_push([KILL]) 23 24 AC_BEFORE([$0], [_AC_COMPILER_EXEEXT]) 25 AC_BEFORE([$0], [AC_LINK_IFELSE]) 26 27 m4_define([_AC_COMPILER_EXEEXT], 28 [AC_LANG_CONFTEST([AC_LANG_PROGRAM()]) 29 # FIXME: Cleanup? 30 AS_IF([AC_TRY_EVAL(ac_link)], [gcc_no_link=no], [gcc_no_link=yes]) 31 if test x$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= 37 else 38 ]m4_defn([_AC_COMPILER_EXEEXT])dnl 39 fi 40 ) 41 42 m4_define([AC_LINK_IFELSE], 43 if test x$gcc_no_link = xyes; then 44 AC_MSG_ERROR([Link tests are not allowed after [[$0]].]) 45 fi 46 m4_defn([AC_LINK_IFELSE])) 47 48 dnl This is a shame. We have to provide a default for some link tests, 49 dnl similar to the default for run tests. 50 m4_define([AC_FUNC_MMAP], 51 if test x$gcc_no_link = xyes; then 52 if test "x${ac_cv_func_mmap_fixed_mapped+set}" != xset; then 53 ac_cv_func_mmap_fixed_mapped=no 54 fi 55 fi 56 if test "x${ac_cv_func_mmap_fixed_mapped}" != xno; then 57 m4_defn([AC_FUNC_MMAP]) 58 fi) 59 60 m4_divert_pop()dnl 61 ])# GCC_NO_EXECUTABLES 62 63 # Use the strongest available test out of AC_TRY_COMPILE and AC_TRY_LINK. 64 AC_DEFUN([GCC_TRY_COMPILE_OR_LINK], 65 [if test x$gcc_no_link = xyes; then 66 AC_TRY_COMPILE([$1], [$2], [$3], [$4]) 67 else 68 AC_TRY_LINK([$1], [$2], [$3], [$4]) 69 fi]) 70
