Limit <config.h>’s includes

This follows up on recent problems with the fact that config.h
includes stdlib.h etc.; some files need to include stdlib.h later.
config.h generally should limit itself to includes that are
universally safe; outside of MS-Windows, only stdbool.h makes
the cut among the files currently included.  So, move the
other includes to just the files that need them (Bug#24506).
* configure.ac (config_opsysfile): Remove, as this generic hook
is no longer needed.
* lib-src/etags.c, src/unexmacosx.c, src/w32.c, src/w32notify.c:
* src/w32proc.c (_GNU_SOURCE):
Remove, as it’s OK for config.h to do this now.
* src/conf_post.h: Include <ms-w32.h>, instead of the generic
config_opsysfile, for simplicity as this old way of configuring is
now done only for the MS-Windows port.  Do not include <ms-w32.h>
if DEFER_MS_W32_H, for the benefit of the few files that want its
effects later.  Do not include <alloca.h>, <string.h>, or
<stdlib.h>.  Other files modified to include these headers as
needed, or to not include headers that are no longer needed.
* src/lisp.h: Include <alloca.h> and <string.h> here, since
some of the inline functions need them.
* src/regex.c: Include <alloca.h> if not emacs.  (If emacs,
we can rely on SAFE_ALLOCA.)  There is no longer any need to
worry about HAVE_ALLOCA_H.
* src/unexmacosx.c: Rely on config.h not including stdlib.h.
* src/w32.c, src/w32notify.c, src/w32proc.c (DEFER_MS_W32_H):
Define before including <config.h> first, and include <ms-w32.h>
after the troublesome headers.

configure.ac

@@ -4882,14 +4882,6 @@ AC_DEFINE_UNQUOTED(EMACS_CONFIGURATION,  "${canonical}",
 		   [Define to the canonical Emacs configuration name.])
 AC_DEFINE_UNQUOTED(EMACS_CONFIG_OPTIONS, "${emacs_config_options}",
 		   [Define to the options passed to configure.])
-AH_TEMPLATE(config_opsysfile, [Some platforms that do not use configure
-  define this to include extra configuration information.])
-
-case $opsys in
-  mingw32)
-    AC_DEFINE(config_opsysfile, <ms-w32.h>, [])
-    ;;
-esac
 
 XMENU_OBJ=
 XOBJ=

lib-src/emacsclient.c

@@ -74,6 +74,7 @@ char *w32_getenv (const char *);
 #include <stdarg.h>
 #include <ctype.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <getopt.h>
 #include <unistd.h>
 

lib-src/etags.c

@@ -90,10 +90,6 @@ char pot_etags_version[] = "@(#) pot revision number is 17.38.1.4";
 
 #include <config.h>
 
-#ifndef _GNU_SOURCE
-# define _GNU_SOURCE 1		/* enables some compiler checks on GNU */
-#endif
-
 /* WIN32_NATIVE is for XEmacs.
    MSDOS, WINDOWSNT, DOS_NT are for Emacs. */
 #ifdef WIN32_NATIVE

lib-src/hexl.c

@@ -22,6 +22,8 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <config.h>
 
 #include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 #include <ctype.h>
 
 #include <binary-io.h>

lib-src/make-docfile.c

@@ -37,11 +37,11 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <config.h>
 
 #include <stdarg.h>
-#include <stdbool.h>
 #include <stddef.h>
 #include <stdint.h>
 #include <stdio.h>
-#include <stdlib.h>   /* config.h unconditionally includes this anyway */
+#include <stdlib.h>
+#include <string.h>
 
 #ifdef WINDOWSNT
 /* Defined to be sys_fopen in ms-w32.h, but only #ifdef emacs, so this

lib-src/movemail.c

@@ -59,8 +59,8 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <sys/file.h>
-#include <stdbool.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <errno.h>
 #include <time.h>
 

lib-src/pop.c

@@ -63,10 +63,12 @@ void sys_freeaddrinfo (struct addrinfo * ai);
 extern struct servent *hes_getservbyname (/* char *, char * */);
 #endif
 
+#include <alloca.h>
 #include <pwd.h>
 #include <netdb.h>
 #include <errno.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
 

lib-src/profile.c

@@ -35,6 +35,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include <inttypes.h>
 #include <stdio.h>
+#include <stdlib.h>
 
 #include <intprops.h>
 #include <systime.h>

lib-src/update-game-score.c

@@ -37,7 +37,6 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <errno.h>
 #include <inttypes.h>
 #include <limits.h>
-#include <stdbool.h>
 #include <string.h>
 #include <stdlib.h>
 #include <stdio.h>

lib/openat-die.c

@@ -2,5 +2,6 @@
    This should never happen with Emacs.  */
 #include <config.h>
 #include "openat.h"
+#include <stdlib.h>
 void openat_save_fail (int errnum) { abort (); }
 void openat_restore_fail (int errnum) { abort (); }

lwlib/lwlib-Xm.c

@@ -22,6 +22,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include <unistd.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <setjmp.h>
 
 #include <X11/StringDefs.h>

lwlib/lwlib.c

@@ -26,6 +26,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include <sys/types.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include "lwlib-int.h"
 #include "lwlib-utils.h"
 #include <X11/StringDefs.h>

src/alloc.c

@@ -22,6 +22,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include <errno.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <limits.h>		/* For CHAR_BIT.  */
 #include <signal.h>		/* For SIGABRT, SIGDANGER.  */
 

src/buffer.c

@@ -25,6 +25,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <sys/param.h>
 #include <errno.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <unistd.h>
 
 #include <verify.h>

src/callproc.c

@@ -22,6 +22,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <config.h>
 #include <errno.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <sys/types.h>
 #include <unistd.h>
 

src/charset.c

@@ -30,6 +30,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include <errno.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <unistd.h>
 #include <limits.h>
 #include <sys/types.h>

src/conf_post.h

@@ -18,22 +18,23 @@ GNU General Public License for more details.
 You should have received a copy of the GNU General Public License
 along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
-/* Commentary:
+/* Put the code here rather than in configure.ac using AH_BOTTOM.
+   This way, the code does not get processed by autoheader.  For
+   example, undefs here are not commented out.
 
-   Rather than writing this code directly in AH_BOTTOM, we include it
-   via this file.  This is so that it does not get processed by
-   autoheader.  Eg, any undefs here would otherwise be commented out.
-*/
-
-/* Code: */
-
-/* Include any platform specific configuration file.  */
-#ifdef config_opsysfile
-# include config_opsysfile
-#endif
+   To help make dependencies clearer elsewhere, this file typically
+   does not #include other files.  The exceptions are first stdbool.h
+   because it is unlikely to interfere with configuration and bool is
+   such a core part of the C language, and second ms-w32.h (DOS_NT
+   only) because it historically was included here and changing that
+   would take some work.  */
 
 #include <stdbool.h>
 
+#if defined DOS_NT && !defined DEFER_MS_W32_H
+# include <ms-w32.h>
+#endif
+
 /* GNUC_PREREQ (V, W, X) is true if this is GNU C version V.W.X or later.
    It can be used in a preprocessor expression.  */
 #ifndef __GNUC_MINOR__
@@ -55,14 +56,6 @@ typedef unsigned int bool_bf;
 typedef bool bool_bf;
 #endif
 
-#ifndef WINDOWSNT
-/* On AIX 3 this must be included before any other include file.  */
-#include <alloca.h>
-#if ! HAVE_ALLOCA
-# error "alloca not available on this machine"
-#endif
-#endif
-
 /* Simulate __has_attribute on compilers that lack it.  It is used only
    on arguments like alloc_size that are handled in this simulation.  */
 #ifndef __has_attribute
@@ -239,9 +232,6 @@ extern void _DebPrint (const char *fmt, ...);
 extern char *emacs_getenv_TZ (void);
 extern int emacs_setenv_TZ (char const *);
 
-#include <string.h>
-#include <stdlib.h>
-
 #if __GNUC__ >= 3  /* On GCC 3.0 we might get a warning.  */
 #define NO_INLINE __attribute__((noinline))
 #else
@@ -365,5 +355,3 @@ extern int emacs_setenv_TZ (char const *);
 #else
 # define UNINIT /* empty */
 #endif
-
-/* conf_post.h ends here */

src/dbusbind.c

@@ -20,6 +20,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #ifdef HAVE_DBUS
 #include <stdio.h>
+#include <stdlib.h>
 #include <dbus/dbus.h>
 
 #include "lisp.h"

src/dispnew.c

@@ -21,6 +21,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <config.h>
 
 #include "sysstdio.h"
+#include <stdlib.h>
 #include <unistd.h>
 
 #include "lisp.h"

src/doprnt.c

@@ -103,6 +103,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include <config.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <float.h>
 #include <unistd.h>
 #include <limits.h>

src/editfns.c

@@ -49,6 +49,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <limits.h>
 
 #include <intprops.h>
+#include <stdlib.h>
 #include <strftime.h>
 #include <verify.h>
 

src/emacs-module.c

@@ -21,11 +21,9 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include "emacs-module.h"
 
-#include <stdbool.h>
 #include <stddef.h>
 #include <stdint.h>
 #include <stdio.h>
-#include <string.h>
 
 #include "lisp.h"
 #include "dynlib.h"

src/emacs.c

@@ -24,6 +24,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <errno.h>
 #include <fcntl.h>
 #include <stdio.h>
+#include <stdlib.h>
 
 #include <sys/types.h>
 #include <sys/file.h>

src/eval.c

@@ -22,6 +22,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <config.h>
 #include <limits.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include "lisp.h"
 #include "blockinput.h"
 #include "commands.h"

src/filelock.c

@@ -27,6 +27,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <sys/stat.h>
 #include <signal.h>
 #include <stdio.h>
+#include <stdlib.h>
 
 #ifdef HAVE_PWD_H
 #include <pwd.h>

src/fns.c

@@ -20,6 +20,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include <config.h>
 
+#include <stdlib.h>
 #include <unistd.h>
 #include <filevercmp.h>
 #include <intprops.h>

src/font.c

@@ -23,6 +23,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <config.h>
 #include <float.h>
 #include <stdio.h>
+#include <stdlib.h>
 
 #include <c-ctype.h>
 

src/fontset.c

@@ -26,6 +26,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include <config.h>
 #include <stdio.h>
+#include <stdlib.h>
 
 #include "lisp.h"
 #include "blockinput.h"

src/frame.c

@@ -20,6 +20,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <config.h>
 
 #include <stdio.h>
+#include <stdlib.h>
 #include <errno.h>
 #include <limits.h>
 

src/keymap.c

@@ -41,6 +41,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include <config.h>
 #include <stdio.h>
+#include <stdlib.h>
 
 #include "lisp.h"
 #include "commands.h"

src/lisp.h

@@ -21,10 +21,12 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #ifndef EMACS_LISP_H
 #define EMACS_LISP_H
 
+#include <alloca.h>
 #include <setjmp.h>
 #include <stdalign.h>
 #include <stdarg.h>
 #include <stddef.h>
+#include <string.h>
 #include <float.h>
 #include <inttypes.h>
 #include <limits.h>

src/lread.c

@@ -23,6 +23,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include <config.h>
 #include "sysstdio.h"
+#include <stdlib.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <sys/file.h>

src/process.c

@@ -22,6 +22,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <config.h>
 
 #include <stdio.h>
+#include <stdlib.h>
 #include <errno.h>
 #include <sys/types.h>		/* Some typedefs are used in sys/file.h.  */
 #include <sys/file.h>

src/regex.c

@@ -50,6 +50,7 @@
 #include <config.h>
 
 #include <stddef.h>
+#include <stdlib.h>
 
 #ifdef emacs
 /* We need this for `regex.h', and perhaps for the Emacs include files.  */
@@ -443,25 +444,12 @@ init_syntax_once (void)
 
 #else /* not REGEX_MALLOC  */
 
-/* Emacs already defines alloca, sometimes.  */
-# ifndef alloca
-
-/* Make alloca work the best possible way.  */
-#  ifdef __GNUC__
-#   define alloca __builtin_alloca
-#  else /* not __GNUC__ */
-#   ifdef HAVE_ALLOCA_H
-#    include <alloca.h>
-#   endif /* HAVE_ALLOCA_H */
-#  endif /* not __GNUC__ */
-
-# endif /* not alloca */
-
 # ifdef emacs
 #  define REGEX_USE_SAFE_ALLOCA USE_SAFE_ALLOCA
 #  define REGEX_SAFE_FREE() SAFE_FREE ()
 #  define REGEX_ALLOCATE SAFE_ALLOCA
 # else
+#  include <alloca.h>
 #  define REGEX_ALLOCATE alloca
 # endif
 

src/sysdep.c

@@ -26,6 +26,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <grp.h>
 #endif /* HAVE_PWD_H */
 #include <limits.h>
+#include <stdlib.h>
 #include <unistd.h>
 
 #include <c-ctype.h>

src/systty.h

@@ -26,7 +26,6 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <fcntl.h>
 #endif /* not DOS_NT */
 
-#include <stdbool.h>
 #include <sys/ioctl.h>
 
 #ifdef HPUX

src/term.c

@@ -23,6 +23,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <errno.h>
 #include <fcntl.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <sys/file.h>
 #include <sys/time.h>
 #include <unistd.h>

src/unexcw.c

@@ -21,7 +21,6 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <config.h>
 #include "unexec.h"
 #include "lisp.h"
-#include <string.h>
 #include <stdio.h>
 #include <fcntl.h>
 #include <a.out.h>

src/unexmacosx.c

@@ -85,20 +85,16 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
    be changed accordingly.
 */
 
-/* Enable GNU extensions in gnulib replacement headers.  */
-#define _GNU_SOURCE 1
-
-/* config.h #define:s malloc/realloc/free and then includes stdlib.h.
-   We want the undefined versions, but if config.h includes stdlib.h
-   with the #define:s in place, the prototypes will be wrong and we get
-   warnings.  To prevent that, include stdlib.h before config.h.  */
-
-#include <stdlib.h>
 #include <config.h>
+
+/* Although <config.h> redefines malloc to unexec_malloc, etc., this
+   file wants stdlib.h to declare the originals.  */
 #undef malloc
 #undef realloc
 #undef free
 
+#include <stdlib.h>
+
 #include "unexec.h"
 #include "lisp.h"
 

src/w32.c

@@ -21,8 +21,8 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
    Geoff Voelker (voelker@cs.washington.edu)                         7-29-94
 */
 
-/* Enable GNU extensions in gnulib replacement headers.  */
-#define _GNU_SOURCE 1
+#define DEFER_MS_W32_H
+#include <config.h>
 
 #include <mingw_time.h>
 #include <stddef.h> /* for offsetof */
@@ -40,9 +40,9 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <sys/utime.h>
 #include <math.h>
 
-/* must include CRT headers *before* config.h */
+/* Include CRT headers *before* ms-w32.h.  */
+#include <ms-w32.h>
 
-#include <config.h>
 #include <mbstring.h>	/* for _mbspbrk, _mbslwr, _mbsrchr, ... */
 
 #undef access

src/w32notify.c

@@ -81,14 +81,14 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
    thread to exit.  The main thread waits for some time for the worker
    thread to exit, and if it doesn't, terminates it forcibly.  */
 
-/* Enable GNU extensions in gnulib replacement headers.  */
-#define _GNU_SOURCE 1
+#define DEFER_MS_W32_H
+#include <config.h>
 
 #include <stddef.h>
 #include <errno.h>
 
-/* must include CRT headers *before* config.h */
-#include <config.h>
+/* Include CRT headers *before* ms-w32.h.  */
+#include <ms-w32.h>
 
 #include <windows.h>
 

src/w32proc.c

@@ -22,8 +22,8 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
      Adapted from alarm.c by Tim Fleehart
 */
 
-/* Enable GNU extensions in gnulib replacement headers.  */
-#define _GNU_SOURCE 1
+#define DEFER_MS_W32_H
+#include <config.h>
 
 #include <mingw_time.h>
 #include <stdio.h>
@@ -38,8 +38,8 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <mbstring.h>
 #include <locale.h>
 
-/* must include CRT headers *before* config.h */
-#include <config.h>
+/* Include CRT headers *before* ms-w32.h.  */
+#include <ms-w32.h>
 
 #undef signal
 #undef wait

src/widget.c

@@ -32,6 +32,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include "widget.h"
 
 #include <stdio.h>
+#include <stdlib.h>
 
 #include "lisp.h"
 #include "xterm.h"

src/xdisp.c

@@ -288,6 +288,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include <config.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <limits.h>
 
 #include "lisp.h"

src/xfaces.c

@@ -200,6 +200,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
    used to fill in unspecified attributes of the default face.  */
 
 #include <config.h>
+#include <stdlib.h>
 #include "sysstdio.h"
 #include <sys/types.h>
 #include <sys/stat.h>

src/xfns.c

@@ -19,6 +19,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include <config.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <math.h>
 #include <unistd.h>
 

src/xfont.c

@@ -21,6 +21,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include <config.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <X11/Xlib.h>
 
 #include "lisp.h"

src/xgselect.c

@@ -25,7 +25,6 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include <glib.h>
 #include <errno.h>
-#include <stdbool.h>
 #include "blockinput.h"
 #include "systime.h"
 

src/xterm.c

@@ -22,6 +22,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include <config.h>
 #include <stdio.h>
+#include <stdlib.h>
 #ifdef USE_CAIRO
 #include <math.h>
 #endif