c.m4

MSYS在windows下模拟了一个类unix的终端

# option to output variable @code{CC} to make it so.  This macro tries
# various options that select ANSI C on some system or another.  It
# considers the compiler to be in ANSI C mode if it handles function
# prototypes correctly.
AC_DEFUN([_AC_PROG_CC_STDC],
[AC_MSG_CHECKING([for $CC option to accept ANSI C])
AC_CACHE_VAL(ac_cv_prog_cc_stdc,
[ac_cv_prog_cc_stdc=no
ac_save_CC=$CC
AC_LANG_CONFTEST([AC_LANG_PROGRAM(
[[#include <stdarg.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
/* Most of the following tests are stolen from RCS 5.7's src/conf.sh.  */
struct buf { int x; };
FILE * (*rcsopen) (struct buf *, struct stat *, int);
static char *e (p, i)
     char **p;
     int i;
{
  return p[i];
}
static char *f (char * (*g) (char **, int), char **p, ...)
{
  char *s;
  va_list v;
  va_start (v,p);
  s = g (p, va_arg (v,int));
  va_end (v);
  return s;
}
int test (int i, double x);
struct s1 {int (*f) (int a);};
struct s2 {int (*f) (double a);};
int pairnames (int, char **, FILE *(*)(struct buf *, struct stat *, int), int, int);
int argc;
char **argv;]],
[[return f (e, argv, 0) != argv[0]  ||  f (e, argv, 1) != argv[1];]])])
# Don't try gcc -ansi; that turns off useful extensions and
# breaks some systems' header files.
# AIX			-qlanglvl=ansi
# Ultrix and OSF/1	-std1
# HP-UX 10.20 and later	-Ae
# HP-UX older versions	-Aa -D_HPUX_SOURCE
# SVR4			-Xc -D__EXTENSIONS__
for ac_arg in "" -qlanglvl=ansi -std1 -Ae "-Aa -D_HPUX_SOURCE" "-Xc -D__EXTENSIONS__"
do
  CC="$ac_save_CC $ac_arg"
  _AC_COMPILE_IFELSE([],
                     [ac_cv_prog_cc_stdc=$ac_arg
break])
done
rm -f conftest.$ac_ext conftest.$ac_objext
CC=$ac_save_CC
])
case "x$ac_cv_prog_cc_stdc" in
  x|xno)
    AC_MSG_RESULT([none needed]) ;;
  *)
    AC_MSG_RESULT([$ac_cv_prog_cc_stdc])
    CC="$CC $ac_cv_prog_cc_stdc" ;;
esac
])# _AC_PROG_CC_STDC


# AC_PROG_CC_STDC
# ---------------
# Has been merged into AC_PROG_CC.
AU_DEFUN([AC_PROG_CC_STDC], [])


# AC_C_BACKSLASH_A
# ----------------
AC_DEFUN([AC_C_BACKSLASH_A],
[
  AC_CACHE_CHECK([whether backslash-a works in strings], ac_cv_c_backslash_a,
   [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([],
     [[
#if '\a' == 'a'
      syntax error;
#endif
      char buf['\a' == 'a' ? -1 : 1];
      buf[0] = '\a';
      return buf[0] != "\a"[0];
     ]])],
     [ac_cv_c_backslash_a=yes],
     [ac_cv_c_backslash_a=no])])
  if test $ac_cv_c_backslash_a = yes; then
    AC_DEFINE(HAVE_C_BACKSLASH_A, 1,
      [Define if backslash-a works in C strings.])
  fi
])


# AC_C_CROSS
# ----------
# Has been merged into AC_PROG_CC.
AU_DEFUN([AC_C_CROSS], [])


# AC_C_CHAR_UNSIGNED
# ------------------
AC_DEFUN([AC_C_CHAR_UNSIGNED],
[AH_VERBATIM([__CHAR_UNSIGNED__],
[/* Define to 1 if type `char' is unsigned and you are not using gcc.  */
#ifndef __CHAR_UNSIGNED__
# undef __CHAR_UNSIGNED__
#endif])dnl
AC_CACHE_CHECK(whether char is unsigned, ac_cv_c_char_unsigned,
[AC_COMPILE_IFELSE([AC_LANG_BOOL_COMPILE_TRY([AC_INCLUDES_DEFAULT([])],
                                             [((char) -1) < 0])],
                   ac_cv_c_char_unsigned=no, ac_cv_c_char_unsigned=yes)])
if test $ac_cv_c_char_unsigned = yes && test "$GCC" != yes; then
  AC_DEFINE(__CHAR_UNSIGNED__)
fi
])# AC_C_CHAR_UNSIGNED


# AC_C_LONG_DOUBLE
# ----------------
AC_DEFUN([AC_C_LONG_DOUBLE],
[AC_CACHE_CHECK(
   [for working long double with more range or precision than double],
   [ac_cv_c_long_double],
   [AC_COMPILE_IFELSE(
      [AC_LANG_BOOL_COMPILE_TRY(
	 [#include <float.h>
	  long double foo = 0.0;],
	 [/* Using '|' rather than '||' catches a GCC 2.95.2 x86 bug.  */
          (DBL_MAX < LDBL_MAX) | (LDBL_EPSILON < DBL_EPSILON)
	  | (DBL_MAX_EXP < LDBL_MAX_EXP) | (DBL_MANT_DIG < LDBL_MANT_DIG)])],
      ac_cv_c_long_double=yes,
      ac_cv_c_long_double=no)])
if test $ac_cv_c_long_double = yes; then
  AC_DEFINE(HAVE_LONG_DOUBLE, 1,
            [Define to 1 if long double works and has more range or precision than double.])
fi
])# AC_C_LONG_DOUBLE


# AC_C_BIGENDIAN ([ACTION-IF-TRUE], [ACTION-IF-FALSE], [ACTION-IF-UNKNOWN])
# -------------------------------------------------------------------------
AC_DEFUN([AC_C_BIGENDIAN],
[AC_CACHE_CHECK(whether byte ordering is bigendian, ac_cv_c_bigendian,
[# See if sys/param.h defines the BYTE_ORDER macro.
AC_COMPILE_IFELSE([AC_LANG_PROGRAM([#include <sys/types.h>
#include <sys/param.h>
],
[#if !BYTE_ORDER || !BIG_ENDIAN || !LITTLE_ENDIAN
 bogus endian macros
#endif
])],
[# It does; now see whether it defined to BIG_ENDIAN or not.
AC_COMPILE_IFELSE([AC_LANG_PROGRAM([#include <sys/types.h>
#include <sys/param.h>
], [#if BYTE_ORDER != BIG_ENDIAN
 not big endian
#endif
])], [ac_cv_c_bigendian=yes], [ac_cv_c_bigendian=no])],
[# It does not; compile a test program.
AC_RUN_IFELSE(
[AC_LANG_SOURCE([[int
main ()
{
  /* Are we little or big endian?  From Harbison&Steele.  */
  union
  {
    long l;
    char c[sizeof (long)];
  } u;
  u.l = 1;
  exit (u.c[sizeof (long) - 1] == 1);
}]])],
              [ac_cv_c_bigendian=no],
              [ac_cv_c_bigendian=yes],
[# try to guess the endianness by grepping values into an object file
  ac_cv_c_bigendian=unknown
  AC_COMPILE_IFELSE([AC_LANG_PROGRAM(
[[short ascii_mm[] = { 0x4249, 0x4765, 0x6E44, 0x6961, 0x6E53, 0x7953, 0 };
short ascii_ii[] = { 0x694C, 0x5454, 0x656C, 0x6E45, 0x6944, 0x6E61, 0 };
void _ascii () { char *s = (char *) ascii_mm; s = (char *) ascii_ii; }
short ebcdic_ii[] = { 0x89D3, 0xE3E3, 0x8593, 0x95C5, 0x89C4, 0x9581, 0 };
short ebcdic_mm[] = { 0xC2C9, 0xC785, 0x95C4, 0x8981, 0x95E2, 0xA8E2, 0 };
void _ebcdic () { char *s = (char *) ebcdic_mm; s = (char *) ebcdic_ii; }]],
[[ _ascii (); _ebcdic (); ]])],
[if grep BIGenDianSyS conftest.$ac_objext >/dev/null ; then
  ac_cv_c_bigendian=yes
fi
if grep LiTTleEnDian conftest.$ac_objext >/dev/null ; then
  if test "$ac_cv_c_bigendian" = unknown; then
    ac_cv_c_bigendian=no
  else
    # finding both strings is unlikely to happen, but who knows?
    ac_cv_c_bigendian=unknown
  fi
fi])])])])
case $ac_cv_c_bigendian in
  yes)
    m4_default([$1],
      [AC_DEFINE([WORDS_BIGENDIAN], 1,
        [Define to 1 if your processor stores words with the most significant
	 byte first (like Motorola and SPARC, unlike Intel and VAX).])]) ;;
  no)
    $2 ;;
  *)
    m4_default([$3],
      [AC_MSG_ERROR([unknown endianness
presetting ac_cv_c_bigendian=no (or yes) will help])]) ;;
esac
])# AC_C_BIGENDIAN


# AC_C_INLINE
# -----------
# Do nothing if the compiler accepts the inline keyword.
# Otherwise define inline to __inline__ or __inline if one of those work,
# otherwise define inline to be empty.
#
# HP C version B.11.11.04 doesn't allow a typedef as the return value for an
# inline function, only builtin types.
#
AN_IDENTIFIER([inline], [AC_C_INLINE])
AC_DEFUN([AC_C_INLINE],
[AC_CACHE_CHECK([for inline], ac_cv_c_inline,
[ac_cv_c_inline=no
for ac_kw in inline __inline__ __inline; do
  AC_COMPILE_IFELSE([AC_LANG_SOURCE(
[#ifndef __cplusplus
typedef int foo_t;
static $ac_kw foo_t static_foo () {return 0; }
$ac_kw foo_t foo () {return 0; }
#endif
])],
                    [ac_cv_c_inline=$ac_kw; break])
done
])
case $ac_cv_c_inline in
  inline | yes) ;;
  no) AC_DEFINE(inline,,
                [Define as `__inline' if that's what the C compiler calls it,
                 or to nothing if it is not supported.]) ;;
  *)  AC_DEFINE_UNQUOTED(inline, $ac_cv_c_inline) ;;
esac
])# AC_C_INLINE


# AC_C_CONST
# ----------
AN_IDENTIFIER([const],  [AC_C_CONST])
AC_DEFUN([AC_C_CONST],
[AC_CACHE_CHECK([for an ANSI C-conforming const], ac_cv_c_const,
[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([],
[[/* FIXME: Include the comments suggested by Paul. */
#ifndef __cplusplus
  /* Ultrix mips cc rejects this.  */
  typedef int charset[2];
  const charset x;
  /* SunOS 4.1.1 cc rejects this.  */
  char const *const *ccp;
  char **p;
  /* NEC SVR4.0.2 mips cc rejects this.  */
  struct point {int x, y;};
  static struct point const zero = {0,0};
  /* AIX XL C 1.02.0.0 rejects this.
     It does not let you subtract one const X* pointer from another in
     an arm of an if-expression whose if-part is not a constant
     expression */
  const char *g = "string";
  ccp = &g + (g ? g-g : 0);
  /* HPUX 7.0 cc rejects these. */
  ++ccp;
  p = (char**) ccp;
  ccp = (char const *const *) p;
  { /* SCO 3.2v4 cc rejects this.  */
    char *t;
    char const *s = 0 ? (char *) 0 : (char const *) 0;

    *t++ = 0;
  }
  { /* Someone thinks the Sun supposedly-ANSI compiler will reject this.  */
    int x[] = {25, 17};
    const int *foo = &x[0];
    ++foo;
  }
  { /* Sun SC1.0 ANSI compiler rejects this -- but not the above. */
    typedef const int *iptr;
    iptr p = 0;
    ++p;
  }
  { /* AIX XL C 1.02.0.0 rejects this saying
       "k.c", line 2.27: 1506-025 (S) Operand must be a modifiable lvalue. */
    struct s { int j; const int *ap[3]; };
    struct s *b; b->j = 5;
  }
  { /* ULTRIX-32 V3.1 (Rev 9) vcc rejects this */
    const int foo = 10;
  }
#endif
]])],
                   [ac_cv_c_const=yes],
                   [ac_cv_c_const=no])])
if test $ac_cv_c_const = no; then
  AC_DEFINE(const,,
            [Define to empty if `const' does not conform to ANSI C.])
fi
])# AC_C_CONST


# AC_C_VOLATILE
# -------------
# Note that, unlike const, #defining volatile to be the empty string can
# actually turn a correct program into an incorrect one, since removing
# uses of volatile actually grants the compiler permission to perform
# optimizations that could break the user's code.  So, do not #define
# volatile away unless it is really necessary to allow the user's code
# to compile cleanly.  Benign compiler failures should be tolerated.
AN_IDENTIFIER([volatile], [AC_C_VOLATILE])
AC_DEFUN([AC_C_VOLATILE],
[AC_CACHE_CHECK([for working volatile], ac_cv_c_volatile,
[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], [
volatile int x;
int * volatile y;])],
                   [ac_cv_c_volatile=yes],
                   [ac_cv_c_volatile=no])])
if test $ac_cv_c_volatile = no; then
  AC_DEFINE(volatile,,
            [Define to empty if the keyword `volatile' does not work.
             Warning: valid code using `volatile' can become incorrect
             without.  Disable with care.])
fi
])# AC_C_VOLATILE


# AC_C_STRINGIZE
# --------------
# Checks if `#' can be used to glue strings together at the CPP level.
# Defines HAVE_STRINGIZE if positive.
AC_DEFUN([AC_C_STRINGIZE],
[AC_CACHE_CHECK([for preprocessor stringizing operator],
                [ac_cv_c_stringize],
[AC_EGREP_CPP([@%:@teststring],
              [@%:@define x(y) #y

char *s = x(teststring);],
              [ac_cv_c_stringize=no],
              [ac_cv_c_stringize=yes])])
if test $ac_cv_c_stringize = yes; then
  AC_DEFINE(HAVE_STRINGIZE, 1,
            [Define to 1 if cpp supports the ANSI @%:@ stringizing operator.])
fi
])# AC_C_STRINGIZE


# AC_C_PROTOTYPES
# ---------------
# Check if the C compiler supports prototypes, included if it needs
# options.
AC_DEFUN([AC_C_PROTOTYPES],
[AC_REQUIRE([AC_PROG_CC])dnl
AC_MSG_CHECKING([for function prototypes])
if test "$ac_cv_prog_cc_stdc" != no; then
  AC_MSG_RESULT([yes])
  AC_DEFINE(PROTOTYPES, 1,
            [Define to 1 if the C compiler supports function prototypes.])
  AC_DEFINE(__PROTOTYPES, 1,
            [Define like PROTOTYPES; this can be used by system headers.])
else
  AC_MSG_RESULT([no])
fi
])# AC_C_PROTOTYPES