Disable stack protector in early static initialization [BZ #7065]

The startup code in csu/, and the brk and sbrk functions are
needed very early in initialization of a statically-linked program,
before the stack guard is initialized; TLS initialization also uses
memcpy, which cannot overrun its own stack.  Mark all of these as
-fno-stack-protector.

We also finally introduce @libc_cv_ssp@ and @no_stack_protector@, both
substituted by the configury changes made earlier, to detect the case
when -fno-stack-protector is supported by the compiler, and
unconditionally pass it in when this is the case, whether or not
--enable-stack-protector is passed to configure.  (This means that
it'll even work when the compiler's been hacked to pass
-fstack-protector by default, unless the hackage is so broken that
it does so in a way that is impossible to override.)

1 files changed, 12 insertions, 0 deletions

diff --git a/ChangeLog b/ChangeLog
index 395a14ba4d..64ccdf7ca0 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,6 +1,18 @@
 2016-12-26  Nick Alcock  <nick.alcock@oracle.com>
 
 	[BZ #7065]
+	* config.make.in (have-ssp, no-stack-protector): New.
+	* csu/Makefile (CFLAGS-.o, CFLAGS-.op, CFLAGS-.os): Use it.
+	* misc/Makefile (CFLAGS-sbrk.o): Likewise.
+	(CFLAGS-sbrk.op): Likewise.
+	(CFLAGS-brk.o): Likewise.
+	(CFLAGS-brk.op): Likewise.
+	* string/Makefile (CFLAGS-memcpy.c): Likewise.
+	(CFLAGS-wordcopy.c): Likewise.
+
+2016-12-26  Nick Alcock  <nick.alcock@oracle.com>
+
+	[BZ #7065]
 	* configure.ac (HAVE_CC_NO_STACK_PROTECTOR): Define.
 	* config.h.in (HAVE_CC_NO_STACK_PROTECTOR): New macro.
 	* include/libc-symbols.h (inhibit_stack_protector): New macro.