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Add gcc 7.3.0 #13

Merged
merged 5 commits into from
Feb 23, 2018
Merged

Add gcc 7.3.0 #13

merged 5 commits into from
Feb 23, 2018

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donald
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@donald donald commented Feb 10, 2018

gcc 7.3 supports -mindirect-branch=thunk-extern which is used (if available) by the kernel build to mitigate Spectre attacks with a method called retpoline. If -mindirect-branch=thunk-extern is not available, the kernel build will not (no longer) emit a warning [1]. The insufficient protection will be visible on the running system

root@dose:/sys# cat /sys/devices/system/cpu/vulnerabilities/spectre_v2 
Vulnerable: Minimal generic ASM retpoline

whereas when the kernel is compiled with gcc 7.3 ( `prun gcc-7.3.0-0 ./linux-4.14.18-207.bee the output is:

root@dose:~# cat /sys/devices/system/cpu/vulnerabilities/spectre_v2 
Mitigation: Full generic retpoline

[1] https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/commit/?h=linux-4.14.y&id=198660b7a5dd33b114001023d540c9072603e2a8

Created by

     cp gcc-7.2.0-0.build.sh gcc-7.3.0-0.build.sh

after which the VERSION= line was updated
gcc doesn't support to be build in the source directory.

https://gcc.gnu.org/wiki/InstallingGCC
This is to support a rebuild during development. Do not fail if target
already exists.
@donald donald merged commit f148782 into master Feb 23, 2018
@david david deleted the add-gcc-7.3.0 branch March 16, 2018 10:43
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