On 3/26/21 4:12 PM, Alexei Starovoitov wrote:

On Fri, Mar 26, 2021 at 4:05 PM Yonghong Song [off-list ref] wrote:

quoted

Now since you found gcc actually has flags in dwarf tag producer which
will provides whether lto is used, I went on clang side found that
the following flag is needed in clang in order to embed flags in
the producer tag:
     -grecord-gcc-switches

...

quoted

    In Linux:
       - add flag -grecord-gcc-switches if clang lto is enabled.

I think that will help to make dwarf output a bit more uniform between
gcc and clang. So it's a good thing on its own.
Recording compilation flags in the debug info could be useful in
other cases too. I would pass it for both lto and non-lto builds.

Good point. Will do this.