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| author | Uros Bizjak <uros@gcc.gnu.org> | 2017-08-08 18:48:46 +0200 |
|---|---|---|
| committer | Uros Bizjak <uros@gcc.gnu.org> | 2017-08-08 18:48:46 +0200 |
| commit | d5bf81b30f7d3faf58d52784013749ca0f9f980f (patch) | |
| tree | b5449885acc699eefc6d35b3d55189c4e773106b /gcc/doc/invoke.texi | |
| parent | 7d27b70bd861d6b83a6821e3fb4205e19a365310 (diff) | |
| download | gcc-d5bf81b30f7d3faf58d52784013749ca0f9f980f.zip gcc-d5bf81b30f7d3faf58d52784013749ca0f9f980f.tar.gz gcc-d5bf81b30f7d3faf58d52784013749ca0f9f980f.tar.bz2 | |
re PR target/81708 (The x86 stack canary location should be customizable)
PR target/81708
* config/i386/i386.opt (mstack-protector-guard-reg=): New option
(mstack-protector-guard-offset=): Ditto.
* config/i386/i386.c (ix86_option_override): Handle
-mstack-protector-guard-reg= and -mstack-protector-guard-offset=
options.
(ix86_stack_protect_guard): Use ix86_stack_protect_guard_reg and
ix86_stack_protect_guard_offset variables.
(TARGET_STACK_PROTECT_GUARD): Always define.
* doc/invoke.texi (x86 Options): Document -mstack-protector-guard-reg=
and -mstack-protector-guard-offset= options.
testsuite/ChangeLog:
PR target/81708
* gcc.target/i386/stack-prot-guard.c: New test.
From-SVN: r250965
Diffstat (limited to 'gcc/doc/invoke.texi')
| -rw-r--r-- | gcc/doc/invoke.texi | 17 |
1 files changed, 15 insertions, 2 deletions
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi index b77de03..cc0f5a0 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -1215,7 +1215,9 @@ See RS/6000 and PowerPC Options. -msse2avx -mfentry -mrecord-mcount -mnop-mcount -m8bit-idiv @gol -mavx256-split-unaligned-load -mavx256-split-unaligned-store @gol -malign-data=@var{type} -mstack-protector-guard=@var{guard} @gol --mmitigate-rop -mgeneral-regs-only -mcall-ms2sysv-xlogues} +-mstack-protector-guard-reg=@var{reg} @gol +-mstack-protector-guard-offset=@var{offset} -mmitigate-rop @gol +-mgeneral-regs-only -mcall-ms2sysv-xlogues} @emph{x86 Windows Options} @gccoptlist{-mconsole -mcygwin -mno-cygwin -mdll @gol @@ -26147,12 +26149,23 @@ to 255, 8-bit unsigned integer divide is used instead of Split 32-byte AVX unaligned load and store. @item -mstack-protector-guard=@var{guard} -@opindex mstack-protector-guard=@var{guard} +@itemx -mstack-protector-guard-reg=@var{reg} +@itemx -mstack-protector-guard-offset=@var{offset} +@opindex mstack-protector-guard +@opindex mstack-protector-guard-reg +@opindex mstack-protector-guard-offset Generate stack protection code using canary at @var{guard}. Supported locations are @samp{global} for global canary or @samp{tls} for per-thread canary in the TLS block (the default). This option has effect only when @option{-fstack-protector} or @option{-fstack-protector-all} is specified. +With the latter choice the options +@option{-mstack-protector-guard-reg=@var{reg}} and +@option{-mstack-protector-guard-offset=@var{offset}} furthermore specify +which segment register (@code{%fs} or @code{%gs}) to use as base register +for reading the canary, and from what offset from that base register. +The default for those is as specified in the relevant ABI. + @item -mmitigate-rop @opindex mmitigate-rop Try to avoid generating code sequences that contain unintended return |