gnulib-tool: Better isolation between different gnulib-tool invocations. * gnulib-tool: New option --witness-c-macro. (witness_c_macro): New variable. (func_emit_lib_Makefile_am): If --witness-c-macro was specified, let AM_CPPFLAGS define it as a C macro. (func_emit_tests_Makefile_am): Likewise. (func_import): Store witness_c_macro setting in gnulib-cache.m4 and read it from there. * m4/gnulib-common.m4 (gl_MODULE_INDICATOR_CONDITION): Define through m4_define, not AC_DEFUN. (gl_MODULE_INDICATOR_SET_VARIABLE_AUX, gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR): New macros. (gl_MODULE_INDICATOR_SET_VARIABLE): Use them. * modules/arpa_inet (Makefile.am): Use sed expression s/.../.../, not s|...|...|, to substitute the values of the GNULIB_* module indicator variables. * modules/dirent (Makefile.am): Likewise. * modules/fcntl-h (Makefile.am): Likewise. * modules/iconv-h (Makefile.am): Likewise. * modules/langinfo (Makefile.am): Likewise. * modules/locale (Makefile.am): Likewise. * modules/math (Makefile.am): Likewise. * modules/netdb (Makefile.am): Likewise. * modules/poll-h (Makefile.am): Likewise. * modules/pty (Makefile.am): Likewise. * modules/search (Makefile.am): Likewise. * modules/signal (Makefile.am): Likewise. * modules/spawn (Makefile.am): Likewise. * modules/stdio (Makefile.am): Likewise. * modules/stdlib (Makefile.am): Likewise. * modules/string (Makefile.am): Likewise. * modules/sys_ioctl (Makefile.am): Likewise. * modules/sys_select (Makefile.am): Likewise. * modules/sys_socket (Makefile.am): Likewise. * modules/sys_stat (Makefile.am): Likewise. * modules/sys_times (Makefile.am): Likewise. * modules/sys_utsname (Makefile.am): Likewise. * modules/sys_wait (Makefile.am): Likewise. * modules/termios (Makefile.am): Likewise. * modules/time (Makefile.am): Likewise. * modules/unistd (Makefile.am): Likewise. * modules/wchar (Makefile.am): Likewise.

# sigpipe.m4 serial 2
dnl Copyright (C) 2008-2011 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.

dnl Tests whether SIGPIPE is provided by <signal.h>.
dnl Sets gl_cv_header_signal_h_SIGPIPE.
AC_DEFUN([gl_SIGNAL_SIGPIPE],
[
  dnl Use AC_REQUIRE here, so that the default behavior below is expanded
  dnl once only, before all statements that occur in other macros.
  AC_REQUIRE([gl_SIGNAL_SIGPIPE_BODY])
])

AC_DEFUN([gl_SIGNAL_SIGPIPE_BODY],
[
  AC_REQUIRE([AC_PROG_CC])
  AC_CACHE_CHECK([for SIGPIPE], [gl_cv_header_signal_h_SIGPIPE], [
    AC_EGREP_CPP([booboo],[
#include <signal.h>
#if !defined SIGPIPE
booboo
#endif
      ],
      [gl_cv_header_signal_h_SIGPIPE=no],
      [gl_cv_header_signal_h_SIGPIPE=yes])
  ])
])