src/conf_post.h

   1 /* conf_post.h --- configure.ac includes this via AH_BOTTOM
   2
   3 Copyright (C) 1988, 1993-1994, 1999-2002, 2004-2017 Free Software
   4 Foundation, Inc.
   5
   6 This file is part of GNU Emacs.
   7
   8 GNU Emacs is free software: you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation, either version 3 of the License, or (at
  11 your option) any later version.
  12
  13 GNU Emacs is distributed in the hope that it will be useful,
  14 but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 GNU General Public License for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
  20
  21 /* Put the code here rather than in configure.ac using AH_BOTTOM.
  22    This way, the code does not get processed by autoheader.  For
  23    example, undefs here are not commented out.
  24
  25    To help make dependencies clearer elsewhere, this file typically
  26    does not #include other files.  The exceptions are first stdbool.h
  27    because it is unlikely to interfere with configuration and bool is
  28    such a core part of the C language, and second ms-w32.h (DOS_NT
  29    only) because it historically was included here and changing that
  30    would take some work.  */
  31
  32 #include <stdbool.h>
  33
  34 #if defined DOS_NT && !defined DEFER_MS_W32_H
  35 # include <ms-w32.h>
  36 #endif
  37
  38 /* GNUC_PREREQ (V, W, X) is true if this is GNU C version V.W.X or later.
  39    It can be used in a preprocessor expression.  */
  40 #ifndef __GNUC_MINOR__
  41 # define GNUC_PREREQ(v, w, x) false
  42 #elif ! defined __GNUC_PATCHLEVEL__
  43 # define GNUC_PREREQ(v, w, x) \
  44     ((v) < __GNUC__ + ((w) < __GNUC_MINOR__ + ((x) == 0))
  45 #else
  46 # define GNUC_PREREQ(v, w, x) \
  47     ((v) < __GNUC__ + ((w) < __GNUC_MINOR__ + ((x) <= __GNUC_PATCHLEVEL__)))
  48 #endif
  49
  50 /* The type of bool bitfields.  Needed to compile Objective-C with
  51    standard GCC.  It was also needed to port to pre-C99 compilers,
  52    although we don't care about that any more.  */
  53 #if NS_IMPL_GNUSTEP
  54 typedef unsigned int bool_bf;
  55 #else
  56 typedef bool bool_bf;
  57 #endif
  58
  59 /* Simulate __has_attribute on compilers that lack it.  It is used only
  60    on arguments like alloc_size that are handled in this simulation.
  61    __has_attribute should be used only in #if expressions, as Oracle
  62    Studio 12.5's __has_attribute does not work in plain code.  */
  63 #ifndef __has_attribute
  64 # define __has_attribute(a) __has_attribute_##a
  65 # define __has_attribute_alloc_size GNUC_PREREQ (4, 3, 0)
  66 # define __has_attribute_cleanup GNUC_PREREQ (3, 4, 0)
  67 # define __has_attribute_externally_visible GNUC_PREREQ (4, 1, 0)
  68 # define __has_attribute_no_address_safety_analysis false
  69 # define __has_attribute_no_sanitize_address GNUC_PREREQ (4, 8, 0)
  70 #endif
  71
  72 /* Simulate __has_builtin on compilers that lack it.  It is used only
  73    on arguments like __builtin_assume_aligned that are handled in this
  74    simulation.  */
  75 #ifndef __has_builtin
  76 # define __has_builtin(a) __has_builtin_##a
  77 # define __has_builtin___builtin_assume_aligned GNUC_PREREQ (4, 7, 0)
  78 #endif
  79
  80 /* Simulate __has_feature on compilers that lack it.  It is used only
  81    to define ADDRESS_SANITIZER below.  */
  82 #ifndef __has_feature
  83 # define __has_feature(a) false
  84 #endif
  85
  86 /* True if addresses are being sanitized.  */
  87 #if defined __SANITIZE_ADDRESS__ || __has_feature (address_sanitizer)
  88 # define ADDRESS_SANITIZER true
  89 #else
  90 # define ADDRESS_SANITIZER false
  91 #endif
  92
  93 /* Yield PTR, which must be aligned to ALIGNMENT.  */
  94 #if ! __has_builtin (__builtin_assume_aligned)
  95 # define __builtin_assume_aligned(ptr, ...) ((void *) (ptr))
  96 #endif
  97
  98 #ifdef DARWIN_OS
  99 #if defined emacs && !defined CANNOT_DUMP
 100 #define malloc unexec_malloc
 101 #define realloc unexec_realloc
 102 #define free unexec_free
 103 #endif
 104 #endif  /* DARWIN_OS */
 105
 106 /* If HYBRID_MALLOC is defined (e.g., on Cygwin), emacs will use
 107    gmalloc before dumping and the system malloc after dumping.
 108    hybrid_malloc and friends, defined in gmalloc.c, are wrappers that
 109    accomplish this.  */
 110 #ifdef HYBRID_MALLOC
 111 #ifdef emacs
 112 #define malloc hybrid_malloc
 113 #define realloc hybrid_realloc
 114 #define aligned_alloc hybrid_aligned_alloc
 115 #define calloc hybrid_calloc
 116 #define free hybrid_free
 117 #endif
 118 #endif  /* HYBRID_MALLOC */
 119
 120 /* We have to go this route, rather than the old hpux9 approach of
 121    renaming the functions via macros.  The system's stdlib.h has fully
 122    prototyped declarations, which yields a conflicting definition of
 123    srand48; it tries to redeclare what was once srandom to be srand48.
 124    So we go with HAVE_LRAND48 being defined.  */
 125 #ifdef HPUX
 126 #undef srandom
 127 #undef random
 128 #undef HAVE_RANDOM
 129 #undef HAVE_RINT
 130 #endif  /* HPUX */
 131
 132 #ifdef MSDOS
 133 #ifndef __DJGPP__
 134 You lose; /* Emacs for DOS must be compiled with DJGPP */
 135 #endif
 136 #define _NAIVE_DOS_REGS
 137
 138 /* Start of gnulib-related stuff  */
 139
 140 /* lib/ftoastr.c wants strtold, but DJGPP only has _strtold.  DJGPP >
 141    2.03 has it, but it also has _strtold as a stub that jumps to
 142    strtold, so use _strtold in all versions.  */
 143 #define strtold _strtold
 144
 145 #if __DJGPP__ > 2 || __DJGPP_MINOR__ > 3
 146 # define HAVE_LSTAT 1
 147 #else
 148 # define lstat stat
 149 /* DJGPP 2.03 and older don't have the next two.  */
 150 # define EOVERFLOW ERANGE
 151 # define SIZE_MAX  4294967295U
 152 #endif
 153
 154 /* We must intercept 'opendir' calls to stash away the directory name,
 155    so we could reuse it in readlinkat; see msdos.c.  */
 156 #define opendir sys_opendir
 157
 158 /* End of gnulib-related stuff.  */
 159
 160 #define emacs_raise(sig) msdos_fatal_signal (sig)
 161
 162 /* DATA_START is needed by vm-limit.c and unexcoff.c. */
 163 #define DATA_START (&etext + 1)
 164
 165 /* Define one of these for easier conditionals.  */
 166 #ifdef HAVE_X_WINDOWS
 167 /* We need a little extra space, see ../../lisp/loadup.el and the
 168    commentary below, in the non-X branch.  The 140KB number was
 169    measured on GNU/Linux and on MS-Windows.  */
 170 #define SYSTEM_PURESIZE_EXTRA (-170000+140000)
 171 #else
 172 /* We need a little extra space, see ../../lisp/loadup.el.
 173    As of 20091024, DOS-specific files use up 62KB of pure space.  But
 174    overall, we end up wasting 130KB of pure space, because
 175    BASE_PURESIZE starts at 1.47MB, while we need only 1.3MB (including
 176    non-DOS specific files and load history; the latter is about 55K,
 177    but depends on the depth of the top-level Emacs directory in the
 178    directory tree).  Given the unknown policy of different DPMI
 179    hosts regarding loading of untouched pages, I'm not going to risk
 180    enlarging Emacs footprint by another 100+ KBytes.  */
 181 #define SYSTEM_PURESIZE_EXTRA (-170000+90000)
 182 #endif
 183 #endif  /* MSDOS */
 184
 185 /* macOS / GNUstep need a bit more pure memory.  Of the existing knobs,
 186    SYSTEM_PURESIZE_EXTRA seems like the least likely to cause problems.  */
 187 #ifdef HAVE_NS
 188 #if defined NS_IMPL_GNUSTEP
 189 #  define SYSTEM_PURESIZE_EXTRA 30000
 190 #elif defined DARWIN_OS
 191 #  define SYSTEM_PURESIZE_EXTRA 200000
 192 #endif
 193 #endif
 194
 195 #ifdef CYGWIN
 196 #define SYSTEM_PURESIZE_EXTRA 50000
 197 #endif
 198
 199 #if defined HAVE_NTGUI && !defined DebPrint
 200 # ifdef EMACSDEBUG
 201 extern void _DebPrint (const char *fmt, ...);
 202 #  define DebPrint(stuff) _DebPrint stuff
 203 # else
 204 #  define DebPrint(stuff) ((void) 0)
 205 # endif
 206 #endif
 207
 208 #if defined CYGWIN && defined HAVE_NTGUI
 209 # define NTGUI_UNICODE /* Cygwin runs only on UNICODE-supporting systems */
 210 # define _WIN32_WINNT 0x500 /* Win2k */
 211 /* The following was in /usr/include/string.h prior to Cygwin 1.7.33.  */
 212 #ifndef strnicmp
 213 #define strnicmp strncasecmp
 214 #endif
 215 #endif
 216
 217 #ifdef emacs /* Don't do this for lib-src.  */
 218 /* Tell regex.c to use a type compatible with Emacs.  */
 219 #define RE_TRANSLATE_TYPE Lisp_Object
 220 #define RE_TRANSLATE(TBL, C) char_table_translate (TBL, C)
 221 #define RE_TRANSLATE_P(TBL) (!EQ (TBL, make_number (0)))
 222 #endif
 223
 224 /* Tell time_rz.c to use Emacs's getter and setter for TZ.
 225    Only Emacs uses time_rz so this is OK.  */
 226 #define getenv_TZ emacs_getenv_TZ
 227 #define setenv_TZ emacs_setenv_TZ
 228 extern char *emacs_getenv_TZ (void);
 229 extern int emacs_setenv_TZ (char const *);
 230
 231 #if __GNUC__ >= 3  /* On GCC 3.0 we might get a warning.  */
 232 #define NO_INLINE __attribute__((noinline))
 233 #else
 234 #define NO_INLINE
 235 #endif
 236
 237 #if __has_attribute (externally_visible)
 238 #define EXTERNALLY_VISIBLE __attribute__((externally_visible))
 239 #else
 240 #define EXTERNALLY_VISIBLE
 241 #endif
 242
 243 #if GNUC_PREREQ (2, 7, 0)
 244 # define ATTRIBUTE_FORMAT(spec) __attribute__ ((__format__ spec))
 245 #else
 246 # define ATTRIBUTE_FORMAT(spec) /* empty */
 247 #endif
 248
 249 #if GNUC_PREREQ (7, 0, 0)
 250 # define FALLTHROUGH __attribute__ ((__fallthrough__))
 251 #else
 252 # define FALLTHROUGH ((void) 0)
 253 #endif
 254
 255 #if GNUC_PREREQ (4, 4, 0) && defined __GLIBC_MINOR__
 256 # define PRINTF_ARCHETYPE __gnu_printf__
 257 #elif GNUC_PREREQ (4, 4, 0) && defined __MINGW32__
 258 # define PRINTF_ARCHETYPE __ms_printf__
 259 #else
 260 # define PRINTF_ARCHETYPE __printf__
 261 #endif
 262 #define ATTRIBUTE_FORMAT_PRINTF(string_index, first_to_check) \
 263   ATTRIBUTE_FORMAT ((PRINTF_ARCHETYPE, string_index, first_to_check))
 264
 265 #define ATTRIBUTE_CONST _GL_ATTRIBUTE_CONST
 266 #define ATTRIBUTE_UNUSED _GL_UNUSED
 267
 268 #if GNUC_PREREQ (3, 3, 0) && !defined __ICC
 269 # define ATTRIBUTE_MAY_ALIAS __attribute__ ((__may_alias__))
 270 #else
 271 # define ATTRIBUTE_MAY_ALIAS
 272 #endif
 273
 274 /* Declare NAME to be a pointer to an object of type TYPE, initialized
 275    to the address ADDR, which may be of a different type.  Accesses
 276    via NAME may alias with other accesses with the traditional
 277    behavior, even if options like gcc -fstrict-aliasing are used.  */
 278
 279 #define DECLARE_POINTER_ALIAS(name, type, addr) \
 280   type ATTRIBUTE_MAY_ALIAS *name = (type *) (addr)
 281
 282 #if 3 <= __GNUC__
 283 # define ATTRIBUTE_MALLOC __attribute__ ((__malloc__))
 284 #else
 285 # define ATTRIBUTE_MALLOC
 286 #endif
 287
 288 #if __has_attribute (alloc_size)
 289 # define ATTRIBUTE_ALLOC_SIZE(args) __attribute__ ((__alloc_size__ args))
 290 #else
 291 # define ATTRIBUTE_ALLOC_SIZE(args)
 292 #endif
 293
 294 #define ATTRIBUTE_MALLOC_SIZE(args) ATTRIBUTE_MALLOC ATTRIBUTE_ALLOC_SIZE (args)
 295
 296 /* Work around GCC bug 59600: when a function is inlined, the inlined
 297    code may have its addresses sanitized even if the function has the
 298    no_sanitize_address attribute.  This bug is fixed in GCC 4.9.0 and
 299    clang 3.4.  */
 300 #if (! ADDRESS_SANITIZER \
 301      || (GNUC_PREREQ (4, 9, 0) \
 302          || 3 < __clang_major__ + (4 <= __clang_minor__)))
 303 # define ADDRESS_SANITIZER_WORKAROUND /* No workaround needed.  */
 304 #else
 305 # define ADDRESS_SANITIZER_WORKAROUND NO_INLINE
 306 #endif
 307
 308 /* Attribute of functions whose code should not have addresses
 309    sanitized.  */
 310
 311 #if __has_attribute (no_sanitize_address)
 312 # define ATTRIBUTE_NO_SANITIZE_ADDRESS \
 313     __attribute__ ((no_sanitize_address)) ADDRESS_SANITIZER_WORKAROUND
 314 #elif __has_attribute (no_address_safety_analysis)
 315 # define ATTRIBUTE_NO_SANITIZE_ADDRESS \
 316     __attribute__ ((no_address_safety_analysis)) ADDRESS_SANITIZER_WORKAROUND
 317 #else
 318 # define ATTRIBUTE_NO_SANITIZE_ADDRESS
 319 #endif
 320
 321 /* gcc -fsanitize=address does not work with vfork in Fedora 25 x86-64.
 322    For now, assume that this problem occurs on all platforms.  */
 323 #if ADDRESS_SANITIZER && !defined vfork
 324 # define vfork fork
 325 #endif
 326
 327 /* Some versions of GNU/Linux define noinline in their headers.  */
 328 #ifdef noinline
 329 #undef noinline
 330 #endif
 331
 332 /* Use Gnulib's extern-inline module for extern inline functions.
 333    An include file foo.h should prepend FOO_INLINE to function
 334    definitions, with the following overall pattern:
 335
 336       [#include any other .h files first.]
 337       ...
 338       INLINE_HEADER_BEGIN
 339       ...
 340       INLINE int
 341       incr (int i)
 342       {
 343         return i + 1;
 344       }
 345       ...
 346       INLINE_HEADER_END
 347
 348    For every executable, exactly one file that includes the header
 349    should do this:
 350
 351       #define INLINE EXTERN_INLINE
 352
 353    before including config.h or any other .h file.
 354    Other .c files should not define INLINE.
 355    For Emacs, this is done by having emacs.c first '#define INLINE
 356    EXTERN_INLINE' and then include every .h file that uses INLINE.
 357
 358    The INLINE_HEADER_BEGIN and INLINE_HEADER_END suppress bogus
 359    warnings in some GCC versions; see ../m4/extern-inline.m4.
 360
 361    C99 compilers compile functions like 'incr' as C99-style extern
 362    inline functions.  Buggy GCC implementations do something similar with
 363    GNU-specific keywords.  Buggy non-GCC compilers use static
 364    functions, which bloats the code but is good enough.  */
 365
 366 #ifndef INLINE
 367 # define INLINE _GL_INLINE
 368 #endif
 369 #define EXTERN_INLINE _GL_EXTERN_INLINE
 370 #define INLINE_HEADER_BEGIN _GL_INLINE_HEADER_BEGIN
 371 #define INLINE_HEADER_END _GL_INLINE_HEADER_END
 372
 373 /* 'int x UNINIT;' is equivalent to 'int x;', except it cajoles GCC
 374    into not warning incorrectly about use of an uninitialized variable.  */
 375 #if defined GCC_LINT || defined lint
 376 # define UNINIT = {0,}
 377 #else
 378 # define UNINIT /* empty */
 379 #endif