0002-Add-test-for-Wunused-but-set-variable.patch 5.5 KB

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  1. From c0f075bdee5edabf8f19b68e0880fbd249a89653 Mon Sep 17 00:00:00 2001
  2. From: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
  3. Date: Sat, 3 Jan 2015 15:09:59 +0100
  4. Subject: [PATCH] Add test for -Wunused-but-set-variable
  5. The -Wunused-but-set-variable option does not exist in some old gcc
  6. versions (gcc 4.5.x), so using it unconditionally breaks the build
  7. with such compilers.
  8. This commit introduces the AX_CHECK_COMPILE_FLAG m4 macro taken from
  9. the autoconf-archive
  10. (http://git.savannah.gnu.org/gitweb/?p=autoconf-archive.git;a=blob_plain;f=m4/ax_check_compile_flag.m4),
  11. and uses it to detect if the -Wunused-but-set-variable option is
  12. supported, and only uses it in this case.
  13. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
  14. (rebased against v0.1.0)
  15. Signed-off-by: Bernd Kuhls <bernd.kuhls@t-online.de>
  16. (rebased against v0.6.3)
  17. Signed-off-by: Adam Duskett <Aduskett@gmail.com>
  18. ---
  19. Makefile.am | 1 +
  20. configure.ac | 6 ++-
  21. m4/ax_check_compile_flag.m4 | 74 +++++++++++++++++++++++++++++++++++++
  22. 3 files changed, 79 insertions(+), 2 deletions(-)
  23. create mode 100644 m4/ax_check_compile_flag.m4
  24. diff --git a/Makefile.am b/Makefile.am
  25. index f961fdb..3ddbe59 100644
  26. --- a/Makefile.am
  27. +++ b/Makefile.am
  28. @@ -151,6 +151,7 @@ janus_CFLAGS = \
  29. -DEVENTDIR=\"$(eventdir)\" \
  30. -DLOGGERDIR=\"$(loggerdir)\" \
  31. -DCONFDIR=\"$(confdir)\" \
  32. + @GCC_WARN_UNUSED_BUT_SET@ \
  33. $(BORINGSSL_CFLAGS) \
  34. $(NULL)
  35. diff --git a/configure.ac b/configure.ac
  36. index ca17a29..beef91a 100644
  37. --- a/configure.ac
  38. +++ b/configure.ac
  39. @@ -13,6 +13,9 @@ AM_SILENT_RULES([yes])
  40. AC_USE_SYSTEM_EXTENSIONS
  41. AC_PROG_CC
  42. +AX_CHECK_COMPILE_FLAG([-Wunused-but-set-variable],
  43. + [GCC_WARN_UNUSED_BUT_SET=-Wunused-but-set-variable])
  44. +AC_SUBST(GCC_WARN_UNUSED_BUT_SET)
  45. LT_PREREQ([2.2])
  46. LT_INIT
  47. @@ -64,8 +67,7 @@ clang*)
  48. CFLAGS="$CFLAGS \
  49. -Wcast-align \
  50. -Wno-override-init \
  51. - -Wunsafe-loop-optimizations \
  52. - -Wunused-but-set-variable"
  53. + -Wunsafe-loop-optimizations"
  54. esac
  55. JANUS_VERSION=103
  56. diff --git a/m4/ax_check_compile_flag.m4 b/m4/ax_check_compile_flag.m4
  57. new file mode 100644
  58. index 0000000..51df0c0
  59. --- /dev/null
  60. +++ b/m4/ax_check_compile_flag.m4
  61. @@ -0,0 +1,74 @@
  62. +# ===========================================================================
  63. +# http://www.gnu.org/software/autoconf-archive/ax_check_compile_flag.html
  64. +# ===========================================================================
  65. +#
  66. +# SYNOPSIS
  67. +#
  68. +# AX_CHECK_COMPILE_FLAG(FLAG, [ACTION-SUCCESS], [ACTION-FAILURE], [EXTRA-FLAGS], [INPUT])
  69. +#
  70. +# DESCRIPTION
  71. +#
  72. +# Check whether the given FLAG works with the current language's compiler
  73. +# or gives an error. (Warnings, however, are ignored)
  74. +#
  75. +# ACTION-SUCCESS/ACTION-FAILURE are shell commands to execute on
  76. +# success/failure.
  77. +#
  78. +# If EXTRA-FLAGS is defined, it is added to the current language's default
  79. +# flags (e.g. CFLAGS) when the check is done. The check is thus made with
  80. +# the flags: "CFLAGS EXTRA-FLAGS FLAG". This can for example be used to
  81. +# force the compiler to issue an error when a bad flag is given.
  82. +#
  83. +# INPUT gives an alternative input source to AC_COMPILE_IFELSE.
  84. +#
  85. +# NOTE: Implementation based on AX_CFLAGS_GCC_OPTION. Please keep this
  86. +# macro in sync with AX_CHECK_{PREPROC,LINK}_FLAG.
  87. +#
  88. +# LICENSE
  89. +#
  90. +# Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de>
  91. +# Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com>
  92. +#
  93. +# This program is free software: you can redistribute it and/or modify it
  94. +# under the terms of the GNU General Public License as published by the
  95. +# Free Software Foundation, either version 3 of the License, or (at your
  96. +# option) any later version.
  97. +#
  98. +# This program is distributed in the hope that it will be useful, but
  99. +# WITHOUT ANY WARRANTY; without even the implied warranty of
  100. +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
  101. +# Public License for more details.
  102. +#
  103. +# You should have received a copy of the GNU General Public License along
  104. +# with this program. If not, see <http://www.gnu.org/licenses/>.
  105. +#
  106. +# As a special exception, the respective Autoconf Macro's copyright owner
  107. +# gives unlimited permission to copy, distribute and modify the configure
  108. +# scripts that are the output of Autoconf when processing the Macro. You
  109. +# need not follow the terms of the GNU General Public License when using
  110. +# or distributing such scripts, even though portions of the text of the
  111. +# Macro appear in them. The GNU General Public License (GPL) does govern
  112. +# all other use of the material that constitutes the Autoconf Macro.
  113. +#
  114. +# This special exception to the GPL applies to versions of the Autoconf
  115. +# Macro released by the Autoconf Archive. When you make and distribute a
  116. +# modified version of the Autoconf Macro, you may extend this special
  117. +# exception to the GPL to apply to your modified version as well.
  118. +
  119. +#serial 3
  120. +
  121. +AC_DEFUN([AX_CHECK_COMPILE_FLAG],
  122. +[AC_PREREQ(2.59)dnl for _AC_LANG_PREFIX
  123. +AS_VAR_PUSHDEF([CACHEVAR],[ax_cv_check_[]_AC_LANG_ABBREV[]flags_$4_$1])dnl
  124. +AC_CACHE_CHECK([whether _AC_LANG compiler accepts $1], CACHEVAR, [
  125. + ax_check_save_flags=$[]_AC_LANG_PREFIX[]FLAGS
  126. + _AC_LANG_PREFIX[]FLAGS="$[]_AC_LANG_PREFIX[]FLAGS $4 $1"
  127. + AC_COMPILE_IFELSE([m4_default([$5],[AC_LANG_PROGRAM()])],
  128. + [AS_VAR_SET(CACHEVAR,[yes])],
  129. + [AS_VAR_SET(CACHEVAR,[no])])
  130. + _AC_LANG_PREFIX[]FLAGS=$ax_check_save_flags])
  131. +AS_IF([test x"AS_VAR_GET(CACHEVAR)" = xyes],
  132. + [m4_default([$2], :)],
  133. + [m4_default([$3], :)])
  134. +AS_VAR_POPDEF([CACHEVAR])dnl
  135. +])dnl AX_CHECK_COMPILE_FLAGS
  136. --
  137. 2.20.1