This commit refactors how Stack Smashing Protection support is handled
in Buildroot:
*) It turns the BR2_TOOLCHAIN_BUILDROOT_USE_SSP option into an option
that only enables the SSP support in uClibc, when using the internal
toolchain backend.
*) It adds an hidden BR2_TOOLCHAIN_HAS_SSP option that gets enabled
when the toolchain has SSP support. Here we have the usual dance:
glibc/eglibc in internal/external backend always select this
option, in the case of uClibc/internal, it gets selected when
BR2_TOOLCHAIN_BUILDROOT_USE_SSP is enabled, in the case of
uClibc/external, there is a new configuration option that the user
must select (or not) depending on whether the toolchain has SSP
support.
*) It adds a new options BR2_ENABLE_SSP in the "Build options" menu,
to enable the usage of SSP support, by adding
-fstack-protector-all to the CFLAGS.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
c5866be0ad