[Bug lto/95605] New: LTO and object files generated by dtrace -G

[Bug lto/95605] New: LTO and object files generated by dtrace -G

[doko at debian dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95605

            Bug ID: 95605
           Summary: LTO and object files generated by dtrace -G
           Product: gcc
           Version: 10.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: lto
          Assignee: unassigned at gcc dot gnu.org
          Reporter: doko at debian dot org
                CC: marxin at gcc dot gnu.org
  Target Milestone: ---

An object file generated with dtrace -G doesn't have a .gnu.lto_.opts section.
Afaiu the lto linking is supposed to merge all flags used for all compile steps
into the link step, if the flag was used for all .o files.  That results in a
binary built without any options, if these are not present in the link step.

[Bug lto/95605] LTO and object files generated by dtrace -G

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95605

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |WAITING
   Last reconfirmed|                            |2020-06-09

--- Comment #1 from Martin Liška <marxin at gcc dot gnu.org> ---
dtrace is new for me, can you please explain more how it works and what's
expected output?

[Bug lto/95605] LTO and object files generated by dtrace -G

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95605

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |INVALID
             Status|WAITING                     |RESOLVED

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
non-LTO objects are not taken into account here so I belive this isn't the
reason you are not seeing the CF protection enabled.

[Bug lto/95605] LTO and object files generated by dtrace -G

[doko at debian dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95605

--- Comment #3 from Matthias Klose <doko at debian dot org> ---
dtrace -G calls gcc to generate the .o file, and you can use the CC and CFLAGS
environment vars to inject the options you need.  Ugly, but you can avoid that
by passing the appropriate options.