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Diffstat (limited to 'm4/c.m4')
| -rw-r--r-- | m4/c.m4 | 265 |
1 files changed, 265 insertions, 0 deletions
@@ -0,0 +1,265 @@ +# This file is part of Autoconf. -*- Autoconf -*- +# Programming languages support. +# Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006 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. +# +# As a special exception, the Free Software Foundation gives unlimited +# permission to copy, distribute and modify the configure scripts that +# are the output of Autoconf. 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 Autoconf appear in them. The GNU +# General Public License (GPL) does govern all other use of the material +# that constitutes the Autoconf program. +# +# Certain portions of the Autoconf source text are designed to be copied +# (in certain cases, depending on the input) into the output of +# Autoconf. We call these the "data" portions. The rest of the Autoconf +# source text consists of comments plus executable code that decides which +# of the data portions to output in any given case. We call these +# comments and executable code the "non-data" portions. Autoconf never +# copies any of the non-data portions into its output. +# +# This special exception to the GPL applies to versions of Autoconf +# released by the Free Software Foundation. When you make and +# distribute a modified version of Autoconf, you may extend this special +# exception to the GPL to apply to your modified version as well, *unless* +# your modified version has the potential to copy into its output some +# of the text that was the non-data portion of the version that you started +# with. (In other words, unless your change moves or copies text from +# the non-data portions to the data portions.) If your modification has +# such potential, you must delete any notice of this special exception +# to the GPL from your modified version. +# +# Written by David MacKenzie, with help from +# Akim Demaille, Paul Eggert, +# Franc,ois Pinard, Karl Berry, Richard Pixley, Ian Lance Taylor, +# Roland McGrath, Noah Friedman, david d zuhn, and many others. + + +# SETools Note: Fedora Core 5 ships with autoconf 2.59, which +# unfortunately is missing the macro AC_PROG_CC_C99. Therefore +# provide a copy of the one from autoconf 2.61. + + + +## ------------------------------- ## +## 4. Compilers' characteristics. ## +## ------------------------------- ## + + +# -------------------------------- # +# 4b. C compiler characteristics. # +# -------------------------------- # + +# _AC_C_STD_TRY(STANDARD, TEST-PROLOGUE, TEST-BODY, OPTION-LIST, +# ACTION-IF-AVAILABLE, ACTION-IF-UNAVAILABLE) +# -------------------------------------------------------------- +# Check whether the C compiler accepts features of STANDARD (e.g `c89', `c99') +# by trying to compile a program of TEST-PROLOGUE and TEST-BODY. If this fails, +# try again with each compiler option in the space-separated OPTION-LIST; if one +# helps, append it to CC. If eventually successful, run ACTION-IF-AVAILABLE, +# else ACTION-IF-UNAVAILABLE. +AC_DEFUN([_AC_C_STD_TRY], +[AC_MSG_CHECKING([for $CC option to accept ISO ]m4_translit($1, [c], [C])) +AC_CACHE_VAL(ac_cv_prog_cc_$1, +[ac_cv_prog_cc_$1=no +ac_save_CC=$CC +AC_LANG_CONFTEST([AC_LANG_PROGRAM([$2], [$3])]) +for ac_arg in '' $4 +do + CC="$ac_save_CC $ac_arg" + _AC_COMPILE_IFELSE([], [ac_cv_prog_cc_$1=$ac_arg]) + test "x$ac_cv_prog_cc_$1" != "xno" && break +done +rm -f conftest.$ac_ext +CC=$ac_save_CC +])# AC_CACHE_VAL +case "x$ac_cv_prog_cc_$1" in + x) + AC_MSG_RESULT([none needed]) ;; + xno) + AC_MSG_RESULT([unsupported]) ;; + *) + CC="$CC $ac_cv_prog_cc_$1" + AC_MSG_RESULT([$ac_cv_prog_cc_$1]) ;; +esac +AS_IF([test "x$ac_cv_prog_cc_$1" != xno], [$5], [$6]) +])# _AC_C_STD_TRY + + +# _AC_PROG_CC_C99 ([ACTION-IF-AVAILABLE], [ACTION-IF-UNAVAILABLE]) +# ---------------------------------------------------------------- +# If the C compiler is not in ISO C99 mode by default, try to add an +# option to output variable CC to make it so. This macro tries +# various options that select ISO C99 on some system or another. It +# considers the compiler to be in ISO C99 mode if it handles _Bool, +# // comments, flexible array members, inline, long long int, mixed +# code and declarations, named initialization of structs, restrict, +# va_copy, varargs macros, variable declarations in for loops and +# variable length arrays. +AC_DEFUN([_AC_PROG_CC_C99], +[_AC_C_STD_TRY([c99], +[[#include <stdarg.h> +#include <stdbool.h> +#include <stdlib.h> +#include <wchar.h> +#include <stdio.h> + +// Check varargs macros. These examples are taken from C99 6.10.3.5. +#define debug(...) fprintf (stderr, __VA_ARGS__) +#define showlist(...) puts (#__VA_ARGS__) +#define report(test,...) ((test) ? puts (#test) : printf (__VA_ARGS__)) +static void +test_varargs_macros (void) +{ + int x = 1234; + int y = 5678; + debug ("Flag"); + debug ("X = %d\n", x); + showlist (The first, second, and third items.); + report (x>y, "x is %d but y is %d", x, y); +} + +// Check long long types. +#define BIG64 18446744073709551615ull +#define BIG32 4294967295ul +#define BIG_OK (BIG64 / BIG32 == 4294967297ull && BIG64 % BIG32 == 0) +#if !BIG_OK + your preprocessor is broken; +#endif +#if BIG_OK +#else + your preprocessor is broken; +#endif +static long long int bignum = -9223372036854775807LL; +static unsigned long long int ubignum = BIG64; + +struct incomplete_array +{ + int datasize; + double data[]; +}; + +struct named_init { + int number; + const wchar_t *name; + double average; +}; + +typedef const char *ccp; + +static inline int +test_restrict (ccp restrict text) +{ + // See if C++-style comments work. + // Iterate through items via the restricted pointer. + // Also check for declarations in for loops. + for (unsigned int i = 0; *(text+i) != '\0'; ++i) + continue; + return 0; +} + +// Check varargs and va_copy. +static void +test_varargs (const char *format, ...) +{ + va_list args; + va_start (args, format); + va_list args_copy; + va_copy (args_copy, args); + + const char *str; + int number; + float fnumber; + + while (*format) + { + switch (*format++) + { + case 's': // string + str = va_arg (args_copy, const char *); + break; + case 'd': // int + number = va_arg (args_copy, int); + break; + case 'f': // float + fnumber = va_arg (args_copy, double); + break; + default: + break; + } + } + va_end (args_copy); + va_end (args); +} +]], +[[ + // Check bool. + _Bool success = false; + + // Check restrict. + if (test_restrict ("String literal") == 0) + success = true; + char *restrict newvar = "Another string"; + + // Check varargs. + test_varargs ("s, d' f .", "string", 65, 34.234); + test_varargs_macros (); + + // Check flexible array members. + struct incomplete_array *ia = + malloc (sizeof (struct incomplete_array) + (sizeof (double) * 10)); + ia->datasize = 10; + for (int i = 0; i < ia->datasize; ++i) + ia->data[i] = i * 1.234; + + // Check named initializers. + struct named_init ni = { + .number = 34, + .name = L"Test wide string", + .average = 543.34343, + }; + + ni.number = 58; + + int dynamic_array[ni.number]; + dynamic_array[ni.number - 1] = 543; + + // work around unused variable warnings + return (!success || bignum == 0LL || ubignum == 0uLL || newvar[0] == 'x' + || dynamic_array[ni.number - 1] != 543); +]], +dnl Try +dnl GCC -std=gnu99 (unused restrictive modes: -std=c99 -std=iso9899:1999) +dnl AIX -qlanglvl=extc99 (unused restrictive mode: -qlanglvl=stdc99) +dnl Intel ICC -c99 +dnl IRIX -c99 +dnl Solaris (unused because it causes the compiler to assume C99 semantics for +dnl library functions, and this is invalid before Solaris 10: -xc99) +dnl Tru64 -c99 +dnl with extended modes being tried first. +[[-std=gnu99 -c99 -qlanglvl=extc99]], [$1], [$2])[]dnl +])# _AC_PROG_CC_C99 + + +# AC_PROG_CC_C99 +# -------------- +AC_DEFUN([AC_PROG_CC_C99], +[ AC_REQUIRE([AC_PROG_CC])dnl + _AC_PROG_CC_C99 +]) |