configure: add option to disable -fstack-protector flags
The -fstack-protector flag family is useful for ensuring safety and for
debugging, but has a performance impact. Here are some boot time comparisons of
the various versions of -fstack-protector using qemu-system-arm on an x86_64
host:
This patch introduces a configure option to disable the stack protector
entirely, and conditional stack protector flag selection (in order,
based on availability): -fstack-protector-strong, -fstack-protector-all,
no stack protector.
Signed-off-by: Steven Noonan <snoonan@amazon.com> Cc: Anthony Liguori <aliguori@amazon.com> Reviewed-by: Stefan Weil <sw@weilnetz.de>
[Prefer -fstack-protector-all to -fstack-protector, suggested by
Laurent Desnogues. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>