--- /dev/null
+From e4ef92852023f4e2f192d3c47220dc75930a615c Mon Sep 17 00:00:00 2001
+From: Gustavo Zacarias <gustavo@zacarias.com.ar>
+Date: Fri, 11 Sep 2015 16:41:31 -0300
+Subject: [PATCH] build: improve stack protector check
+
+Testing a toolchain for proper -fstack-protector must go beyond ensuring
+the compiler and linker accept the option.
+If the test C program does nothing with the stack then guards aren't
+inserted and/or are optimized away giving the false impression that it
+works when in fact the libc might not support it.
+
+Update the check to a program that uses the stack, hence making a link
+fail if proper support isn't available, for example in non-ssp enabled
+uclibc toolchains like this:
+
+test.c:(.text.startup+0x64): undefined reference to `__stack_chk_fail'
+
+Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
+---
+ buildtools/wafsamba/samba_autoconf.py | 20 +++++++++++++++++---
+ 1 file changed, 17 insertions(+), 3 deletions(-)
+
+diff --git a/buildtools/wafsamba/samba_autoconf.py b/buildtools/wafsamba/samba_autoconf.py
+index c5f132c..ef34b00 100644
+--- a/buildtools/wafsamba/samba_autoconf.py
++++ b/buildtools/wafsamba/samba_autoconf.py
+@@ -657,9 +657,23 @@ def SAMBA_CONFIG_H(conf, path=None):
+ if not IN_LAUNCH_DIR(conf):
+ return
+
+- if conf.CHECK_CFLAGS(['-fstack-protector']) and conf.CHECK_LDFLAGS(['-fstack-protector']):
+- conf.ADD_CFLAGS('-fstack-protector')
+- conf.ADD_LDFLAGS('-fstack-protector')
++ # we need to build real code that can't be optimized away to test
++ if conf.check(fragment='''
++ #include <stdio.h>
++
++ int main(void)
++ {
++ char t[100000];
++ while (fgets(t, sizeof(t), stdin));
++ return 0;
++ }
++ ''',
++ execute=0,
++ ccflags='-fstack-protector',
++ ldflags='-fstack-protector',
++ msg='Checking if toolchain accepts -fstack-protector'):
++ conf.ADD_CFLAGS('-fstack-protector')
++ conf.ADD_LDFLAGS('-fstack-protector')
+
+ if Options.options.debug:
+ conf.ADD_CFLAGS('-g', testflags=True)
+--
+2.4.6
+
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