build: Use AX_CC_FOR_BUILD and EXEEXT.

* configure.ac (AX_CC_FOR_BUILD): New.
* doc/Makefile.am: Use EXEEXT and EXEEXT_FOR_BUILD.
* m4/ac_prog_cc_for_build.m4: Remove.
* m4/ax_cc_for_build.m4: New.

--

Suggested-by: Michael Haubenwallner
	      <michael.haubenwallner@ssi-schaefer.com>
Fixes-commit: 6eb80abcde5ad776379069871e4156b28ef69712
Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>

2 files changed, 77 insertions, 149 deletions

diff --git a/m4/ac_prog_cc_for_build.m4 b/m4/ac_prog_cc_for_build.m4
deleted file mode 100644
index 32329c7..0000000
--- a/m4/ac_prog_cc_for_build.m4
+++ /dev/null
@@ -1,149 +0,0 @@
-dnl Available from the GNU Autoconf Macro Archive at:
-dnl https://www.gnu.org/software/ac-archive/htmldoc/ac_prog_cc_for_build.html
-dnl
-dnl All content of this archive is free software;
-dnl you can redistribute it and/or modify it under the terms of the GNU
-dnl General Public License as published by the Free Software Foundation;
-dnl either version 2, or (at your option) any later version.
-dnl
-dnl As a special exception, the respective Autoconf Macro's copyright
-dnl owner gives unlimited permission to copy, distribute and modify the
-dnl configure scripts that are the output of Autoconf when processing the
-dnl Macro. You need not follow the terms of the GNU General Public License
-dnl when using or distributing such scripts, even though portions of the
-dnl text of the Macro appear in them. The GNU General Public License (GPL)
-dnl does govern all other use of the material that constitutes the
-dnl Autoconf Macro.
-dnl 
-dnl This special exception to the GPL applies to versions of the Autoconf
-dnl Macro released by the GNU Autoconf Macro Archive. When you make and
-dnl distribute a modified version of the Autoconf Macro, you may extend
-dnl this special exception to the GPL to apply to your modified version as
-dnl well.
-
-dnl Synopsis AC_PROG_CC_FOR_BUILD
-dnl
-dnl This macro searches for a C compiler that generates native
-dnl executables, that is a C compiler that surely is not a cross-compiler.
-dnl This can be useful if you have to generate source code at compile-time
-dnl like for example GCC does.
-dnl
-dnl The macro sets the CC_FOR_BUILD and CPP_FOR_BUILD macros to anything
-dnl needed to compile or link (CC_FOR_BUILD) and preprocess
-dnl (CPP_FOR_BUILD).  The value of these variables can be overridden by
-dnl the user by specifying a compiler with an environment variable (like
-dnl you do for standard CC).
-dnl
-dnl It also sets BUILD_EXEEXT and BUILD_OBJEXT to the executable and
-dnl object file extensions for the build platform, and GCC_FOR_BUILD
-dnl to `yes' if the compiler we found is GCC.  All these variables but
-dnl GCC_FOR_BUILD are substituted in the Makefile.
-dnl
-dnl Author Paolo Bonzini <bonzini@gnu.org>
-dnl
-AC_DEFUN([AC_PROG_CC_FOR_BUILD], [dnl
-AC_REQUIRE([AC_PROG_CC])dnl
-AC_REQUIRE([AC_PROG_CPP])dnl
-AC_REQUIRE([AC_EXEEXT])dnl
-AC_REQUIRE([AC_CANONICAL_SYSTEM])dnl
-dnl
-pushdef([AC_TRY_COMPILER], [
-cat > conftest.$ac_ext << EOF
-#line __oline__ "configure"
-#include "confdefs.h"
-[$1]
-EOF
-# If we can't run a trivial program, we are probably using a cross
-compiler.
-# Fail miserably.
-if AC_TRY_EVAL(ac_link) && test -s conftest${ac_exeext} && (./conftest;
-exit) 2>/dev/null; then
-  [$2]=yes
-else
-  echo "configure: failed program was:" >&AC_FD_CC
-  cat conftest.$ac_ext >&AC_FD_CC
-  [$2]=no
-fi
-[$3]=no
-rm -fr conftest*])dnl
-
-dnl Use the standard macros, but make them use other variable names
-dnl
-pushdef([cross_compiling], [#])dnl
-pushdef([ac_cv_prog_CPP], ac_cv_build_prog_CPP)dnl
-pushdef([ac_cv_prog_gcc], ac_cv_build_prog_gcc)dnl
-pushdef([ac_cv_prog_cc_works], ac_cv_build_prog_cc_works)dnl
-pushdef([ac_cv_prog_cc_cross], ac_cv_build_prog_cc_cross)dnl
-pushdef([ac_cv_prog_cc_g], ac_cv_build_prog_cc_g)dnl
-pushdef([ac_cv_exeext], ac_cv_build_exeext)dnl
-pushdef([ac_cv_objext], ac_cv_build_objext)dnl
-pushdef([ac_exeext], ac_build_exeext)dnl
-pushdef([ac_objext], ac_build_objext)dnl
-pushdef([CC], CC_FOR_BUILD)dnl
-pushdef([CPP], CPP_FOR_BUILD)dnl
-pushdef([CFLAGS], CFLAGS_FOR_BUILD)dnl
-pushdef([CPPFLAGS], CPPFLAGS_FOR_BUILD)dnl
-pushdef([host], build)dnl
-pushdef([host_alias], build_alias)dnl
-pushdef([host_cpu], build_cpu)dnl
-pushdef([host_vendor], build_vendor)dnl
-pushdef([host_os], build_os)dnl
-pushdef([ac_cv_host], ac_cv_build)dnl
-pushdef([ac_cv_host_alias], ac_cv_build_alias)dnl
-pushdef([ac_cv_host_cpu], ac_cv_build_cpu)dnl
-pushdef([ac_cv_host_vendor], ac_cv_build_vendor)dnl
-pushdef([ac_cv_host_os], ac_cv_build_os)dnl
-pushdef([ac_cpp], ac_build_cpp)dnl
-pushdef([ac_compile], ac_build_compile)dnl
-pushdef([ac_link], ac_build_link)dnl
-
-dnl Defeat the anti-duplication mechanism
-dnl
-dnl undefine([AC_PROVIDE_AC_PROG_CPP])dnl
-dnl undefine([AC_PROVIDE_AC_PROG_C])dnl
-dnl undefine([AC_PROVIDE_AC_EXEEXT])dnl
-
-AC_PROG_CC
-AC_PROG_CPP
-AC_EXEEXT
-
-dnl Restore the old definitions
-dnl
-popdef([AC_TRY_COMPILER])dnl
-popdef([ac_link])dnl
-popdef([ac_compile])dnl
-popdef([ac_cpp])dnl
-popdef([ac_cv_host_os])dnl
-popdef([ac_cv_host_vendor])dnl
-popdef([ac_cv_host_cpu])dnl
-popdef([ac_cv_host_alias])dnl
-popdef([ac_cv_host])dnl
-popdef([host_os])dnl
-popdef([host_vendor])dnl
-popdef([host_cpu])dnl
-popdef([host_alias])dnl
-popdef([host])dnl
-popdef([CPPFLAGS])dnl
-popdef([CFLAGS])dnl
-popdef([CPP])dnl
-popdef([CC])dnl
-popdef([ac_objext])dnl
-popdef([ac_exeext])dnl
-popdef([ac_cv_objext])dnl
-popdef([ac_cv_exeext])dnl
-popdef([ac_cv_prog_cc_g])dnl
-popdef([ac_cv_prog_cc_works])dnl
-popdef([ac_cv_prog_cc_cross])dnl
-popdef([ac_cv_prog_gcc])dnl
-popdef([ac_cv_prog_CPP])dnl
-popdef([cross_compiling])dnl
-
-dnl Finally, set Makefile variables
-dnl
-BUILD_EXEEXT=$ac_build_exeext
-BUILD_OBJEXT=$ac_build_objext
-AC_SUBST(BUILD_EXEEXT)dnl
-AC_SUBST(BUILD_OBJEXT)dnl
-AC_SUBST([CFLAGS_FOR_BUILD])dnl
-AC_SUBST([CPPFLAGS_FOR_BUILD])dnl
-])
diff --git a/m4/ax_cc_for_build.m4 b/m4/ax_cc_for_build.m4
new file mode 100644
index 0000000..c62ffad
--- /dev/null
+++ b/m4/ax_cc_for_build.m4
@@ -0,0 +1,77 @@
+# ===========================================================================
+#     https://www.gnu.org/software/autoconf-archive/ax_cc_for_build.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_CC_FOR_BUILD
+#
+# DESCRIPTION
+#
+#   Find a build-time compiler. Sets CC_FOR_BUILD and EXEEXT_FOR_BUILD.
+#
+# LICENSE
+#
+#   Copyright (c) 2010 Reuben Thomas <rrt@sc3d.org>
+#   Copyright (c) 1999 Richard Henderson <rth@redhat.com>
+#
+#   This program is free software: you can redistribute it and/or modify it
+#   under the terms of the GNU General Public License as published by the
+#   Free Software Foundation, either version 3 of the License, or (at your
+#   option) any later version.
+#
+#   This program is distributed in the hope that it will be useful, but
+#   WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
+#   Public License for more details.
+#
+#   You should have received a copy of the GNU General Public License along
+#   with this program. If not, see <https://www.gnu.org/licenses/>.
+#
+#   As a special exception, the respective Autoconf Macro's copyright owner
+#   gives unlimited permission to copy, distribute and modify the configure
+#   scripts that are the output of Autoconf when processing the Macro. You
+#   need not follow the terms of the GNU General Public License when using
+#   or distributing such scripts, even though portions of the text of the
+#   Macro appear in them. The GNU General Public License (GPL) does govern
+#   all other use of the material that constitutes the Autoconf Macro.
+#
+#   This special exception to the GPL applies to versions of the Autoconf
+#   Macro released by the Autoconf Archive. When you make and distribute a
+#   modified version of the Autoconf Macro, you may extend this special
+#   exception to the GPL to apply to your modified version as well.
+
+#serial 3
+
+dnl Get a default for CC_FOR_BUILD to put into Makefile.
+AC_DEFUN([AX_CC_FOR_BUILD],
+[# Put a plausible default for CC_FOR_BUILD in Makefile.
+if test -z "$CC_FOR_BUILD"; then
+  if test "x$cross_compiling" = "xno"; then
+    CC_FOR_BUILD='$(CC)'
+  else
+    CC_FOR_BUILD=gcc
+  fi
+fi
+AC_SUBST(CC_FOR_BUILD)
+# Also set EXEEXT_FOR_BUILD.
+if test "x$cross_compiling" = "xno"; then
+  EXEEXT_FOR_BUILD='$(EXEEXT)'
+else
+  AC_CACHE_CHECK([for build system executable suffix], bfd_cv_build_exeext,
+    [rm -f conftest*
+     echo 'int main () { return 0; }' > conftest.c
+     bfd_cv_build_exeext=
+     ${CC_FOR_BUILD} -o conftest conftest.c 1>&5 2>&5
+     for file in conftest.*; do
+       case $file in
+       *.c | *.o | *.obj | *.ilk | *.pdb) ;;
+       *) bfd_cv_build_exeext=`echo $file | sed -e s/conftest//` ;;
+       esac
+     done
+     rm -f conftest*
+     test x"${bfd_cv_build_exeext}" = x && bfd_cv_build_exeext=no])
+  EXEEXT_FOR_BUILD=""
+  test x"${bfd_cv_build_exeext}" != xno && EXEEXT_FOR_BUILD=${bfd_cv_build_exeext}
+fi
+AC_SUBST(EXEEXT_FOR_BUILD)])dnl