--- a/gcc/configure.ac 2014-12-05 00:53:24.000000000 +0100 +++ b/gcc/configure.ac 2015-06-08 23:27:11.744348211 +0200 @@ -5221,6 +5119,25 @@ if test x$gcc_cv_libc_provides_ssp = xye [Define if your target C library provides stack protector support]) fi +# Check whether --enable-default-ssp was given. +AC_ARG_ENABLE(default-ssp, +[AS_HELP_STRING([--enable-default-ssp], + [enable Smart Stack Protection as default])], +if test x$gcc_cv_libc_provides_ssp = xyes; then + case "$target" in + ia64*-*-*) enable_default_ssp=no ;; + *) enable_default_ssp=$enableval ;; + esac +else + enable_default_ssp=no +fi, +enable_default_ssp=no) +if test x$enable_default_ssp == xyes ; then + AC_DEFINE(ENABLE_DEFAULT_SSP, 1, + [Define if your target supports default STACK-PROTECTOR and it is enabled.]) +fi +AC_SUBST([enable_default_ssp]) + # Test for on the target. GCC_TARGET_TEMPLATE([HAVE_SYS_SDT_H]) AC_MSG_CHECKING(sys/sdt.h in the target C library) --- a/gcc/defaults.h 2014-11-01 09:13:09.000000000 +0100 +++ b/gcc/defaults.h 2015-06-08 22:43:18.764269749 +0200 @@ -1263,6 +1263,18 @@ see the files COPYING3 and COPYING.RUNTI #define STACK_SIZE_MODE word_mode #endif +/* Default value for flag_stack_protect when flag_stack_protect is initialized to -1: + --enable-default-ssp: Default flag_stack_protect to -fstack-protector-strong. + --disable-default-ssp: Default flag_stack_protect to 0. + */ +#ifdef ENABLE_DEFAULT_SSP +# ifndef DEFAULT_FLAG_SSP +# define DEFAULT_FLAG_SSP 3 +# endif +#else +# define DEFAULT_FLAG_SSP 0 +#endif + /* Provide default values for the macros controlling stack checking. */ /* The default is neither full builtin stack checking... */ --- a/gcc/common.opt 2014-10-28 11:33:04.000000000 +0100 +++ b/gcc/common.opt 2015-06-08 22:41:30.114266512 +0200 @@ -2054,15 +2054,15 @@ Common RejectNegative Joined Var(common_ -fstack-limit-symbol= Trap if the stack goes past symbol fstack-protector -Common Report Var(flag_stack_protect, 1) +Common Report Var(flag_stack_protect, 1) Init(-1) Use propolice as a stack protection method fstack-protector-all -Common Report RejectNegative Var(flag_stack_protect, 2) +Common Report RejectNegative Var(flag_stack_protect, 2) Init(-1) Use a stack protection method for every function fstack-protector-strong -Common Report RejectNegative Var(flag_stack_protect, 3) +Common Report RejectNegative Var(flag_stack_protect, 3) Init(-1) Use a smart stack protection method for certain functions fstack-protector-explicit -Common Report RejectNegative Var(flag_stack_protect, 4) +Common Report RejectNegative Var(flag_stack_protect, 4) Init(-1) Use stack protection method only for functions with the stack_protect attribute fstack-usage --- a/gcc/opts.c 2014-10-28 11:33:04.000000000 +0100 +++ b/gcc/opts.c 2015-06-27 01:06:48.670870534 +0200 @@ -739,6 +740,1 @@ finish_options (struct gcc_options *opts opts->x_flag_opts_finished = true; } + /* We initialize opts->x_flag_stack_protect to -1 so that targets + can set a default value. */ + if (opts->x_flag_stack_protect == -1) + opts->x_flag_stack_protect = DEFAULT_FLAG_SSP; + if (opts->x_optimize == 0) { /* Inlining does not work if not optimizing,