autoconf/tests/c.at

#							-*- Autotest -*-

AT_BANNER([C low level compiling/preprocessing macros.])

# Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2008, 2009
# Free Software Foundation, Inc.
#
# 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 2, 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, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
# 02110-1301, USA.


# Since the macros which compile are required by most tests, check
# them first.  But remember that looking for a compiler is even more
# primitive, so check those first.


## ------------ ##
## Extensions.  ##
## ------------ ##

# As far as we know only `foo', `foo.exe' are possible executable,
# and `foo.o', `foo.obj' are possible object files.  Autoconf must not
# know that, but it is OK for the test suite to take this into account.
AT_CHECK_MACRO([Extensions],
[[AC_PROG_CC
case $ac_exeext in
  '' | '.exe' ) ;;
  * ) AC_MSG_ERROR([suspicious executable suffix: $ac_exeext]);;
esac

case $ac_objext in
  'o' | 'obj' ) ;;
  * ) AC_MSG_ERROR([suspicious object suffix: $ac_objext]);;
esac
]])



## -------------------------- ##
## Broken/missing compilers.  ##
## -------------------------- ##


# Check that Autoconf correctly diagnoses broken compilers, and in
# particular, if it does not exit 77, the test suite is in trouble...
# FIXME: Once a precise message decided, check stderr of configure.
AT_SETUP([Broken/missing compilers])

AT_DATA([configure.ac],
[[AC_INIT
CC=no-such-compiler
AC_PROG_CC
]])

AT_CHECK_AUTOCONF
AT_CHECK_CONFIGURE([], 77, ignore, ignore)

AT_CLEANUP


## ------------ ##
## C keywords.  ##
## ------------ ##

# GCC supports `const', `typeof', and `volatile'.
AT_CHECK_MACRO([C keywords],
[[AC_PROG_CC
AC_C_CONST
AC_C_TYPEOF
AC_C_VOLATILE
case $GCC,$ac_cv_c_const,$ac_cv_c_typeof,$ac_cv_c_volatile in
 yes,*no*)
   AC_MSG_ERROR([failed to detect `const', `typeof', or `volatile' support]);;
esac
]])



## --------------------------------- ##
## AC_PROG_CPP requires AC_PROG_CC.  ##
## --------------------------------- ##

# Must invoke AC_PROG_CC.
AT_CHECK_MACRO([AC_PROG_CPP requires AC_PROG_CC],
[[AC_PROG_CPP
test -z "$CC" &&
   AC_MSG_ERROR([looked for a C preprocessor without looking for a compiler])
]])



## --------------------------- ##
## AC_PROG_CPP with warnings.  ##
## --------------------------- ##


# It's Ok for strict preprocessors to produce warnings.

AT_SETUP([AC_PROG_CPP with warnings])

AT_DATA([mycpp],
[[#! /bin/sh
echo noise >&2
exec "$@"
]])

chmod +x mycpp

_AT_CHECK_AC_MACRO(
[[AC_PROG_CPP
# If the preprocessor is not strict, just ignore
test "x$ac_c_preproc_warn_flag" = xyes &&
  AC_MSG_ERROR([preprocessor has no warning option], 77)
CPP="./mycpp $CPP"

# Exercise CPP.
AC_CHECK_HEADERS(stdio.h autoconf_io.h, [], [], [-])]])

AT_CHECK_DEFINES(
[/* #undef HAVE_AUTOCONF_IO_H */
#define HAVE_STDIO_H 1
])

AT_CLEANUP


## ------------------------------ ##
## AC_PROG_CPP without warnings.  ##
## ------------------------------ ##

AT_SETUP([AC_PROG_CPP without warnings])

# Ignore if /lib/cpp doesn't work
AT_CHECK([[echo '#include <stdio.h>' | /lib/cpp || exit 77]],
  [], [ignore], [ignore])

# A cpp which exit status is meaningless.
AT_DATA([mycpp],
[[#! /bin/sh
/lib/cpp "$@"
exit 0
]])

chmod +x mycpp

_AT_CHECK_AC_MACRO(
[[CPP=./mycpp
AC_PROG_CPP
test "x$ac_c_preproc_warn_flag" != xyes &&
  AC_MSG_ERROR([failed to detect preprocessor warning option])

# Exercise CPP.
AC_CHECK_HEADERS(stdio.h autoconf_io.h, [], [], [-])]])

AT_CHECK_DEFINES(
[/* #undef HAVE_AUTOCONF_IO_H */
#define HAVE_STDIO_H 1
])

AT_CLEANUP



## -------------------- ##
## AC_PROG_CPP via CC.  ##
## -------------------- ##


# It's Ok for strict preprocessors to produce warnings.

AT_SETUP([AC_PROG_CPP via CC])

# Ignore if /lib/cpp doesn't work
AT_CHECK([[echo '#include <stdio.h>' | /lib/cpp || exit 77]],
  [], [ignore], [ignore])

AT_DATA([mycc],
[[#! /bin/sh
echo "Annoying copyright message" >&2
exec "$@"
]])

chmod +x mycc

# We go through the following contortions, in order to have the
# configure script go down the same codepaths as it would during a
# normal CPP selection check.  If we explicitly set CPP, it goes down
# a different codepath.
_AT_CHECK_AC_MACRO(
[[AC_PROG_CC
CC="./mycc $CC"
AC_PROG_CPP
# The test $CC compiler should have been selected.
test "$CPP" != "$CC -E" &&
  AC_MSG_ERROR([error messages on stderr cause the preprocessor selection to fail])

# Exercise CPP.
AC_CHECK_HEADERS(stdio.h autoconf_io.h, [], [], [-])]])

AT_CHECK_DEFINES(
[/* #undef HAVE_AUTOCONF_IO_H */
#define HAVE_STDIO_H 1
])

AT_CLEANUP


## ------------------------------------ ##
## AC_NO_EXECUTABLES (working linker).  ##
## ------------------------------------ ##

AT_CHECK_MACRO([AC_NO_EXECUTABLES (working linker)],
[AC_NO_EXECUTABLES
AC_PROG_CC
])


## ----------------------------------- ##
## AC_NO_EXECUTABLES (broken linker).  ##
## ----------------------------------- ##

AT_CHECK_MACRO([AC_NO_EXECUTABLES (broken linker)],
[LDFLAGS=-lnosuchlibrary
AC_NO_EXECUTABLES
AC_PROG_CC
])


## -------------------------- ##
## AC_USE_SYSTEM_EXTENSIONS.  ##
## -------------------------- ##

AT_SETUP([AC_USE_SYSTEM_EXTENSIONS])

# Some existing configure.ac mixed AC_AIX (now an alias for
# AC_USE_SYSTEM_EXTENSIONS) and AC_DEFINE([__EXTENSIONS__]), which
# broke autoheader in 2.62.  Test that this is supported.

_AT_CHECK_AC_MACRO(
[[AC_AIX
AC_DEFINE([__EXTENSIONS__], [1], [Manually defined for Solaris])
]])

_AT_CHECK_AC_MACRO(
[[AC_USE_SYSTEM_EXTENSIONS
AC_DEFINE([__EXTENSIONS__], [1], [Manually defined for Solaris])
]])

AT_CLEANUP


## ----------------------- ##
## AC_C_RESTRICT and C++.  ##
## ----------------------- ##

AT_SETUP([AC_C_RESTRICT and C++])

# In some compiler suites, the left hand doesn't know about everything
# the right hand does; or the user mixes the C compiler from one suite
# with the C++ compiler from another.  In this case, Sun WorkShop CC
# not like the _Restrict accepted by cc.

AT_DATA([configure.ac],
[[AC_INIT
AC_PROG_CC
AC_PROG_CXX
AC_C_RESTRICT
AC_CONFIG_HEADERS([config.h])
AC_CONFIG_FILES([Makefile])
AC_OUTPUT
]])

AT_DATA([Makefile.in],
[[CC = @CC@
CXX = @CXX@
CFLAGS = @CFLAGS@
CXXFLAGS = @CXXFLAGS@
CPPFLAGS = -I. @CPPFLAGS@
OBJEXT = @OBJEXT@
all: foo.$(OBJEXT) bar.$(OBJEXT)
cpp-works:
	$(CXX) $(CPPFLAGS) $(CXXFLAGS) -c cpp-works.cpp
foo.$(OBJEXT): foo.c
	$(CC) $(CPPFLAGS) $(CFLAGS) -c foo.c
bar.$(OBJEXT): bar.cpp
	$(CXX) $(CPPFLAGS) $(CXXFLAGS) -c bar.cpp
]])

AT_DATA([foo.c],
[[#include <config.h>

int foo (int * restrict i1, int * restrict i2)
{
  return i1[0] + i2[0];
}
]])

cp foo.c bar.cpp

AT_DATA([cpp-works.cpp],
[[// This file is just to test whether we have a working C++ compiler at all
class foo { int x; };
class foo foobar;
]])

AT_CHECK([autoconf])
AT_CHECK([autoheader])
AT_CHECK([./configure], [], [ignore], [ignore])
AT_CHECK([${MAKE-make} cpp-works || exit 77], [], [ignore], [ignore])
AT_CHECK([${MAKE-make}], [], [ignore], [ignore])

AT_CLEANUP