summaryrefslogtreecommitdiff
path: root/source3/lib/replace/autoconf-2.60.m4
blob: 5360fff5d241360a8c04c03971a57e4732a71da8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
# _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 mixed
# code and declarations, _Bool, inline and restrict.
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>

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 work.
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 = (float) va_arg(args_copy, double);
	  break;
	default:
	  break;
	}
    }
  va_end(args_copy);
  va_end(args);
}
]],
[[
  // Check bool and long long datatypes.
  _Bool success = false;
  long long int bignum = -1234567890LL;
  unsigned long long int ubignum = 1234567890uLL;

  // 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);

  // Check incomplete arrays work.
  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] = (double) i * 1.234;

  // Check named initialisers.
  struct named_init ni = {
    .number = 34,
    .name = L"Test wide string",
    .average = 543.34343,
  };

  ni.number = 58;

  int dynamic_array[ni.number];
  dynamic_array[43] = 543;

  // work around unused variable warnings
  return  bignum == 0LL || ubignum == 0uLL || newvar[0] == 'x';
]],
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
])

# AC_USE_SYSTEM_EXTENSIONS
# ------------------------
# Enable extensions on systems that normally disable them,
# typically due to standards-conformance issues.
AC_DEFUN([AC_USE_SYSTEM_EXTENSIONS],
[
  AC_BEFORE([$0], [AC_COMPILE_IFELSE])
  AC_BEFORE([$0], [AC_RUN_IFELSE])

  AC_REQUIRE([AC_GNU_SOURCE])
  AC_REQUIRE([AC_AIX])
  AC_REQUIRE([AC_MINIX])

  AH_VERBATIM([__EXTENSIONS__],
[/* Enable extensions on Solaris.  */
#ifndef __EXTENSIONS__
# undef __EXTENSIONS__
#endif
#ifndef _POSIX_PTHREAD_SEMANTICS
# undef _POSIX_PTHREAD_SEMANTICS
#endif])
  AC_CACHE_CHECK([whether it is safe to define __EXTENSIONS__],
    [ac_cv_safe_to_define___extensions__],
    [AC_COMPILE_IFELSE(
       [AC_LANG_PROGRAM([
#	  define __EXTENSIONS__ 1
	  AC_INCLUDES_DEFAULT])],
       [ac_cv_safe_to_define___extensions__=yes],
       [ac_cv_safe_to_define___extensions__=no])])
  test $ac_cv_safe_to_define___extensions__ = yes &&
    AC_DEFINE([__EXTENSIONS__])
  AC_DEFINE([_POSIX_PTHREAD_SEMANTICS])
])