[Bug target/84148] New: CET shouldn't be enabled in 32-bit run-time libraries by default

[hjl.tools at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84148

            Bug ID: 84148
           Summary: CET shouldn't be enabled in 32-bit run-time libraries
                    by default
           Product: gcc
           Version: 8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: hjl.tools at gmail dot com
                CC: igor.v.tsimbalist at intel dot com
            Blocks: 81652
  Target Milestone: ---

ENDBR32 and RDSSPD are multi-byte NOPs on x86-64 processors and
newer x86 processors.  They are UD on older 32-bit processors.
We should enable CET in 32-bit run-time libraries only if --enable-cet
is used to configure GCC.


Referenced Bugs:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81652
[Bug 81652] [meta-bug] -fcf-protection=full -mcet bugs