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alloca-opt: Fix conflict mingw's new <alloca.h> file. Reported by Eli Zaretskii <eliz@gnu.org>. * lib/alloca.in.h: On mingw systems that have <alloca.h>, include that. * m4/alloca.m4 (gl_FUNC_ALLOCA): Set HAVE_ALLOCA_H. * modules/alloca-opt (Makefile.am): Substitute HAVE_ALLOCA_H.
author Bruno Haible <bruno@clisp.org>
date Sun, 10 Mar 2019 20:39:34 +0100
parents b06060465f09
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
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1 # alloca.m4 serial 15
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2 dnl Copyright (C) 2002-2004, 2006-2007, 2009-2019 Free Software Foundation,
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3 dnl Inc.
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4 dnl This file is free software; the Free Software Foundation
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5 dnl gives unlimited permission to copy and/or distribute it,
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6 dnl with or without modifications, as long as this notice is preserved.
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7
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8 AC_DEFUN([gl_FUNC_ALLOCA],
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9 [
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10 AC_REQUIRE([AC_FUNC_ALLOCA])
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11 if test $ac_cv_func_alloca_works = no; then
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12 gl_PREREQ_ALLOCA
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13 fi
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14
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15 # Define an additional variable used in the Makefile substitution.
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16 if test $ac_cv_working_alloca_h = yes; then
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17 AC_CACHE_CHECK([for alloca as a compiler built-in], [gl_cv_rpl_alloca], [
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18 AC_EGREP_CPP([Need own alloca], [
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19 #if defined __GNUC__ || defined _AIX || defined _MSC_VER
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20 Need own alloca
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21 #endif
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22 ], [gl_cv_rpl_alloca=yes], [gl_cv_rpl_alloca=no])
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23 ])
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24 if test $gl_cv_rpl_alloca = yes; then
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25 dnl OK, alloca can be implemented through a compiler built-in.
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26 AC_DEFINE([HAVE_ALLOCA], [1],
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27 [Define to 1 if you have 'alloca' after including <alloca.h>,
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28 a header that may be supplied by this distribution.])
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29 ALLOCA_H=alloca.h
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30 else
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31 dnl alloca exists as a library function, i.e. it is slow and probably
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32 dnl a memory leak. Don't define HAVE_ALLOCA in this case.
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33 ALLOCA_H=
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34 fi
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35 else
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36 ALLOCA_H=alloca.h
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37 fi
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38 AC_SUBST([ALLOCA_H])
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39 AM_CONDITIONAL([GL_GENERATE_ALLOCA_H], [test -n "$ALLOCA_H"])
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40
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41 if test $ac_cv_working_alloca_h = yes; then
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42 HAVE_ALLOCA_H=1
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43 else
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44 HAVE_ALLOCA_H=0
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45 fi
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46 AC_SUBST([HAVE_ALLOCA_H])
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47 ])
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48
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49 # Prerequisites of lib/alloca.c.
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50 # STACK_DIRECTION is already handled by AC_FUNC_ALLOCA.
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51 AC_DEFUN([gl_PREREQ_ALLOCA], [:])
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52
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53 # This works around a bug in autoconf <= 2.68.
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54 # See <https://lists.gnu.org/r/bug-gnulib/2011-06/msg00277.html>.
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55
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56 m4_version_prereq([2.69], [] ,[
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57
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58 # This is taken from the following Autoconf patch:
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59 # https://git.savannah.gnu.org/gitweb/?p=autoconf.git;a=commitdiff;h=6cd9f12520b0d6f76d3230d7565feba1ecf29497
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60
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61 # _AC_LIBOBJ_ALLOCA
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62 # -----------------
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63 # Set up the LIBOBJ replacement of 'alloca'. Well, not exactly
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64 # AC_LIBOBJ since we actually set the output variable 'ALLOCA'.
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65 # Nevertheless, for Automake, AC_LIBSOURCES it.
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66 m4_define([_AC_LIBOBJ_ALLOCA],
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67 [# The SVR3 libPW and SVR4 libucb both contain incompatible functions
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68 # that cause trouble. Some versions do not even contain alloca or
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69 # contain a buggy version. If you still want to use their alloca,
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70 # use ar to extract alloca.o from them instead of compiling alloca.c.
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71 AC_LIBSOURCES(alloca.c)
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72 AC_SUBST([ALLOCA], [\${LIBOBJDIR}alloca.$ac_objext])dnl
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73 AC_DEFINE(C_ALLOCA, 1, [Define to 1 if using 'alloca.c'.])
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74
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75 AC_CACHE_CHECK(whether 'alloca.c' needs Cray hooks, ac_cv_os_cray,
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76 [AC_EGREP_CPP(webecray,
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77 [#if defined CRAY && ! defined CRAY2
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78 webecray
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79 #else
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80 wenotbecray
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81 #endif
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82 ], ac_cv_os_cray=yes, ac_cv_os_cray=no)])
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83 if test $ac_cv_os_cray = yes; then
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84 for ac_func in _getb67 GETB67 getb67; do
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85 AC_CHECK_FUNC($ac_func,
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86 [AC_DEFINE_UNQUOTED(CRAY_STACKSEG_END, $ac_func,
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87 [Define to one of '_getb67', 'GETB67',
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88 'getb67' for Cray-2 and Cray-YMP
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89 systems. This function is required for
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90 'alloca.c' support on those systems.])
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91 break])
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92 done
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93 fi
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94
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95 AC_CACHE_CHECK([stack direction for C alloca],
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96 [ac_cv_c_stack_direction],
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97 [AC_RUN_IFELSE([AC_LANG_SOURCE(
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98 [AC_INCLUDES_DEFAULT
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99 int
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100 find_stack_direction (int *addr, int depth)
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101 {
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102 int dir, dummy = 0;
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103 if (! addr)
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104 addr = &dummy;
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105 *addr = addr < &dummy ? 1 : addr == &dummy ? 0 : -1;
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106 dir = depth ? find_stack_direction (addr, depth - 1) : 0;
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107 return dir + dummy;
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108 }
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109
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110 int
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111 main (int argc, char **argv)
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112 {
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113 return find_stack_direction (0, argc + !argv + 20) < 0;
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114 }])],
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115 [ac_cv_c_stack_direction=1],
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116 [ac_cv_c_stack_direction=-1],
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117 [ac_cv_c_stack_direction=0])])
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118 AH_VERBATIM([STACK_DIRECTION],
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119 [/* If using the C implementation of alloca, define if you know the
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120 direction of stack growth for your system; otherwise it will be
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121 automatically deduced at runtime.
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122 STACK_DIRECTION > 0 => grows toward higher addresses
03e2cd1cbbe8 maint: indent with spaces, not TABs, and add a rule to check this
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123 STACK_DIRECTION < 0 => grows toward lower addresses
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Jim Meyering <meyering@redhat.com>
parents: 15304
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124 STACK_DIRECTION = 0 => direction of growth unknown */
15304
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Paul Eggert <eggert@cs.ucla.edu>
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125 @%:@undef STACK_DIRECTION])dnl
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126 AC_DEFINE_UNQUOTED(STACK_DIRECTION, $ac_cv_c_stack_direction)
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127 ])# _AC_LIBOBJ_ALLOCA
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parents: 14528
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128 ])