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-rw-r--r--gnulib-m4/alloca.m486
1 files changed, 80 insertions, 6 deletions
diff --git a/gnulib-m4/alloca.m4 b/gnulib-m4/alloca.m4
index f3ee3438..8408bed2 100644
--- a/gnulib-m4/alloca.m4
+++ b/gnulib-m4/alloca.m4
@@ -1,5 +1,5 @@
-# alloca.m4 serial 9
-dnl Copyright (C) 2002-2004, 2006-2007, 2009-2010 Free Software Foundation,
+# alloca.m4 serial 14
+dnl Copyright (C) 2002-2004, 2006-2007, 2009-2015 Free Software Foundation,
dnl Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
@@ -7,10 +7,6 @@ dnl with or without modifications, as long as this notice is preserved.
AC_DEFUN([gl_FUNC_ALLOCA],
[
- dnl Work around a bug of AC_EGREP_CPP in autoconf-2.57.
- AC_REQUIRE([AC_PROG_CPP])
- AC_REQUIRE([AC_PROG_EGREP])
-
AC_REQUIRE([AC_FUNC_ALLOCA])
if test $ac_cv_func_alloca_works = no; then
gl_PREREQ_ALLOCA
@@ -40,8 +36,86 @@ AC_DEFUN([gl_FUNC_ALLOCA],
ALLOCA_H=alloca.h
fi
AC_SUBST([ALLOCA_H])
+ AM_CONDITIONAL([GL_GENERATE_ALLOCA_H], [test -n "$ALLOCA_H"])
])
# Prerequisites of lib/alloca.c.
# STACK_DIRECTION is already handled by AC_FUNC_ALLOCA.
AC_DEFUN([gl_PREREQ_ALLOCA], [:])
+
+# This works around a bug in autoconf <= 2.68.
+# See <http://lists.gnu.org/archive/html/bug-gnulib/2011-06/msg00277.html>.
+
+m4_version_prereq([2.69], [] ,[
+
+# This is taken from the following Autoconf patch:
+# http://git.savannah.gnu.org/cgit/autoconf.git/commit/?id=6cd9f12520b0d6f76d3230d7565feba1ecf29497
+
+# _AC_LIBOBJ_ALLOCA
+# -----------------
+# Set up the LIBOBJ replacement of 'alloca'. Well, not exactly
+# AC_LIBOBJ since we actually set the output variable 'ALLOCA'.
+# Nevertheless, for Automake, AC_LIBSOURCES it.
+m4_define([_AC_LIBOBJ_ALLOCA],
+[# The SVR3 libPW and SVR4 libucb both contain incompatible functions
+# that cause trouble. Some versions do not even contain alloca or
+# contain a buggy version. If you still want to use their alloca,
+# use ar to extract alloca.o from them instead of compiling alloca.c.
+AC_LIBSOURCES(alloca.c)
+AC_SUBST([ALLOCA], [\${LIBOBJDIR}alloca.$ac_objext])dnl
+AC_DEFINE(C_ALLOCA, 1, [Define to 1 if using 'alloca.c'.])
+
+AC_CACHE_CHECK(whether 'alloca.c' needs Cray hooks, ac_cv_os_cray,
+[AC_EGREP_CPP(webecray,
+[#if defined CRAY && ! defined CRAY2
+webecray
+#else
+wenotbecray
+#endif
+], ac_cv_os_cray=yes, ac_cv_os_cray=no)])
+if test $ac_cv_os_cray = yes; then
+ for ac_func in _getb67 GETB67 getb67; do
+ AC_CHECK_FUNC($ac_func,
+ [AC_DEFINE_UNQUOTED(CRAY_STACKSEG_END, $ac_func,
+ [Define to one of '_getb67', 'GETB67',
+ 'getb67' for Cray-2 and Cray-YMP
+ systems. This function is required for
+ 'alloca.c' support on those systems.])
+ break])
+ done
+fi
+
+AC_CACHE_CHECK([stack direction for C alloca],
+ [ac_cv_c_stack_direction],
+[AC_RUN_IFELSE([AC_LANG_SOURCE(
+[AC_INCLUDES_DEFAULT
+int
+find_stack_direction (int *addr, int depth)
+{
+ int dir, dummy = 0;
+ if (! addr)
+ addr = &dummy;
+ *addr = addr < &dummy ? 1 : addr == &dummy ? 0 : -1;
+ dir = depth ? find_stack_direction (addr, depth - 1) : 0;
+ return dir + dummy;
+}
+
+int
+main (int argc, char **argv)
+{
+ return find_stack_direction (0, argc + !argv + 20) < 0;
+}])],
+ [ac_cv_c_stack_direction=1],
+ [ac_cv_c_stack_direction=-1],
+ [ac_cv_c_stack_direction=0])])
+AH_VERBATIM([STACK_DIRECTION],
+[/* If using the C implementation of alloca, define if you know the
+ direction of stack growth for your system; otherwise it will be
+ automatically deduced at runtime.
+ STACK_DIRECTION > 0 => grows toward higher addresses
+ STACK_DIRECTION < 0 => grows toward lower addresses
+ STACK_DIRECTION = 0 => direction of growth unknown */
+@%:@undef STACK_DIRECTION])dnl
+AC_DEFINE_UNQUOTED(STACK_DIRECTION, $ac_cv_c_stack_direction)
+])# _AC_LIBOBJ_ALLOCA
+])