m4/pdns_pie.m4

   1 dnl
   2 dnl Check for support for position independent executables
   3 dnl
   4 dnl Copyright (C) 2013 Red Hat, Inc.
   5 dnl
   6 dnl This library is free software; you can redistribute it and/or
   7 dnl modify it under the terms of the GNU Lesser General Public
   8 dnl License as published by the Free Software Foundation; either
   9 dnl version 2.1 of the License, or (at your option) any later version.
  10 dnl
  11 dnl This library is distributed in the hope that it will be useful,
  12 dnl but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 dnl Lesser General Public License for more details.
  15 dnl
  16 dnl You should have received a copy of the GNU Lesser General Public
  17 dnl License along with this library.  If not, see
  18 dnl <http://www.gnu.org/licenses/>.
  19 dnl
  20
  21 AC_DEFUN([AC_CC_PIE],[
  22     AC_REQUIRE([gl_UNKNOWN_WARNINGS_ARE_ERRORS])
  23     PIE_CFLAGS=
  24     PIE_LDFLAGS=
  25     OLD_CXXFLAGS=$CXXFLAGS
  26     case "$host" in
  27       *-*-mingw* | *-*-msvc* | *-*-cygwin* )
  28          ;; dnl All code is position independent on Win32 target
  29       *)
  30         CXXFLAGS="-fPIE -DPIE"
  31         gl_COMPILER_OPTION_IF([-pie], [
  32           PIE_CFLAGS="-fPIE -DPIE"
  33           PIE_LDFLAGS="-pie"
  34           ], [
  35             dnl some versions of clang require -Wl,-pie instead of -pie
  36             gl_COMPILER_OPTION_IF([[-Wl,-pie]], [
  37               PIE_CFLAGS="-fPIE -DPIE"
  38               PIE_LDFLAGS="-Wl,-pie"
  39               ], [],
  40               [AC_LANG_PROGRAM([[
  41 #include <pthread.h>
  42 __thread unsigned int t_id;
  43                 ]], [[t_id = 1;]])]
  44             )
  45           ],
  46           [AC_LANG_PROGRAM([[
  47 #include <pthread.h>
  48 __thread unsigned int t_id;
  49             ]], [[t_id = 1;]])]
  50         )
  51     esac
  52     CXXFLAGS=$OLD_CXXFLAGS
  53     AC_SUBST([PIE_CFLAGS])
  54     AC_SUBST([PIE_LDFLAGS])
  55 ])