annotate src/libsndfile-1.0.27/M4/stack_protect.m4 @ 81:7029a4916348

Merge build update
author Chris Cannam
date Thu, 31 Oct 2019 13:36:58 +0000
parents 1df64224f5ac
children
rev   line source
Chris@40 1 dnl Copyright (C) 2013 Xiph.org Foundation
Chris@40 2 dnl
Chris@40 3 dnl Redistribution and use in source and binary forms, with or without
Chris@40 4 dnl modification, are permitted provided that the following conditions
Chris@40 5 dnl are met:
Chris@40 6 dnl
Chris@40 7 dnl - Redistributions of source code must retain the above copyright
Chris@40 8 dnl notice, this list of conditions and the following disclaimer.
Chris@40 9 dnl
Chris@40 10 dnl - Redistributions in binary form must reproduce the above copyright
Chris@40 11 dnl notice, this list of conditions and the following disclaimer in the
Chris@40 12 dnl documentation and/or other materials provided with the distribution.
Chris@40 13 dnl
Chris@40 14 dnl - Neither the name of the Xiph.org Foundation nor the names of its
Chris@40 15 dnl contributors may be used to endorse or promote products derived from
Chris@40 16 dnl this software without specific prior written permission.
Chris@40 17 dnl
Chris@40 18 dnl THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
Chris@40 19 dnl ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
Chris@40 20 dnl LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
Chris@40 21 dnl A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR
Chris@40 22 dnl CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
Chris@40 23 dnl EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
Chris@40 24 dnl PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
Chris@40 25 dnl PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
Chris@40 26 dnl LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
Chris@40 27 dnl NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
Chris@40 28 dnl SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
Chris@40 29
Chris@40 30 dnl Want to know of GCC stack protector works, botfor the C and for the C++
Chris@40 31 dnl compiler.
Chris@40 32 dnl
Chris@40 33 dnl Just checking if the compiler accepts the required CFLAGSs is not enough
Chris@40 34 dnl because we have seen at least one instance where this check was
Chris@40 35 dnl in-sufficient.
Chris@40 36 dnl
Chris@40 37 dnl Instead, try to compile and link a test program with the stack protector
Chris@40 38 dnl flags. If that works, we use it.
Chris@40 39
Chris@40 40 AC_DEFUN([XIPH_GCC_STACK_PROTECTOR],
Chris@40 41 [AC_LANG_ASSERT(C)
Chris@40 42 AC_MSG_CHECKING([if $CC supports stack smash protection])
Chris@40 43 xiph_stack_check_old_cflags="$CFLAGS"
Chris@40 44 SSP_FLAGS="-fstack-protector --param ssp-buffer-size=4"
Chris@40 45 CFLAGS=$SSP_FLAGS
Chris@40 46 AC_TRY_LINK([
Chris@40 47 #include <stdio.h>
Chris@40 48 ],
Chris@40 49 [puts("Hello, World!"); return 0;],
Chris@40 50 AC_MSG_RESULT([yes])
Chris@40 51 CFLAGS="$xiph_stack_check_old_cflags $SSP_FLAGS",
Chris@40 52 AC_MSG_RESULT([no])
Chris@40 53 CFLAGS="$xiph_stack_check_old_cflags"
Chris@40 54 )
Chris@40 55 ])# XIPH_GCC_STACK_PROTECTOR
Chris@40 56
Chris@40 57 AC_DEFUN([XIPH_GXX_STACK_PROTECTOR],
Chris@40 58 [AC_LANG_PUSH([C++])
Chris@40 59 AC_MSG_CHECKING([if $CXX supports stack smash protection])
Chris@40 60 xiph_stack_check_old_cflags="$CFLAGS"
Chris@40 61 SSP_FLAGS="-fstack-protector --param ssp-buffer-size=4"
Chris@40 62 CFLAGS=$SSP_FLAGS
Chris@40 63 AC_TRY_LINK([
Chris@40 64 #include <cstdio>
Chris@40 65 ],
Chris@40 66 [puts("Hello, World!"); return 0;],
Chris@40 67 AC_MSG_RESULT([yes])
Chris@40 68 CFLAGS="$xiph_stack_check_old_cflags $SSP_FLAGS",
Chris@40 69 AC_MSG_RESULT([no])
Chris@40 70 CFLAGS="$xiph_stack_check_old_cflags"
Chris@40 71 )
Chris@40 72 AC_LANG_POP([C++])
Chris@40 73 ])# XIPH_GXX_STACK_PROTECTOR