We have a couple of bugs open about our CFLAGS.
1) https://bugs.archlinux.org/task/44361 -Remove the no-op --param=ssp-buffer-size=4 switch from CFLAGS Since we moved from -fstack-protector to -fstack-protector-strong, this paramater is unused and can be removed.
2) https://bugs.archlinux.org/task/44362 - Add -fstack-check Read more about this here: https://gcc.gnu.org/onlinedocs/gccint/Stack-Checking.html This is essentially a no-op for most code, so should have no real performance hit. I can not find any benchmarks to demonstrate that though.
This would mean: CFLAGS="-march=x86-64 -mtune=generic -O2 -pipe -fstack-protector-strong -fstack-check"
Opinions?
Allan
On Mon, Jul 27, 2015 at 6:15 AM, Allan McRae allan@archlinux.org wrote:
We have a couple of bugs open about our CFLAGS.
- https://bugs.archlinux.org/task/44361 -Remove the no-op
--param=ssp-buffer-size=4 switch from CFLAGS Since we moved from -fstack-protector to -fstack-protector-strong, this paramater is unused and can be removed.
- https://bugs.archlinux.org/task/44362 - Add -fstack-check
Read more about this here: https://gcc.gnu.org/onlinedocs/gccint/Stack-Checking.html This is essentially a no-op for most code, so should have no real performance hit. I can not find any benchmarks to demonstrate that though.
This would mean: CFLAGS="-march=x86-64 -mtune=generic -O2 -pipe -fstack-protector-strong -fstack-check"
Opinions?
Seems sound given our focus on IA32 (don't know about other architectures). +1 from me.
On 27/07, Jan Alexander Steffens wrote:
On Mon, Jul 27, 2015 at 6:15 AM, Allan McRae allan@archlinux.org wrote:
We have a couple of bugs open about our CFLAGS.
- https://bugs.archlinux.org/task/44361 -Remove the no-op
--param=ssp-buffer-size=4 switch from CFLAGS Since we moved from -fstack-protector to -fstack-protector-strong, this paramater is unused and can be removed.
- https://bugs.archlinux.org/task/44362 - Add -fstack-check
Read more about this here: https://gcc.gnu.org/onlinedocs/gccint/Stack-Checking.html This is essentially a no-op for most code, so should have no real performance hit. I can not find any benchmarks to demonstrate that though.
This would mean: CFLAGS="-march=x86-64 -mtune=generic -O2 -pipe -fstack-protector-strong -fstack-check"
Opinions?
Seems sound given our focus on IA32 (don't know about other architectures). +1 from me.
Our focus on IA32?
-fstack-check works very well on x86 and x86_64 but is quite buggy on other architectures like ARM. I'm not quite sure if that was the point being made though.
On 28/07/15 05:42, Jan Alexander Steffens wrote:
On Mon, Jul 27, 2015 at 6:15 AM, Allan McRae allan@archlinux.org wrote:
We have a couple of bugs open about our CFLAGS.
- https://bugs.archlinux.org/task/44361 -Remove the no-op
--param=ssp-buffer-size=4 switch from CFLAGS Since we moved from -fstack-protector to -fstack-protector-strong, this paramater is unused and can be removed.
- https://bugs.archlinux.org/task/44362 - Add -fstack-check
Read more about this here: https://gcc.gnu.org/onlinedocs/gccint/Stack-Checking.html This is essentially a no-op for most code, so should have no real performance hit. I can not find any benchmarks to demonstrate that though.
This would mean: CFLAGS="-march=x86-64 -mtune=generic -O2 -pipe -fstack-protector-strong -fstack-check"
Opinions?
Seems sound given our focus on IA32 (don't know about other architectures). +1 from me.
Any other comments before I rebuild pacman with these changes?
Allan
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