[Bug debug/97989] -g3 somehow breaks -E

[stsp at users dot sourceforge.net]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97989

--- Comment #14 from Stas Sergeev <stsp at users dot sourceforge.net> ---
(In reply to Jakub Jelinek from comment #13)
> Because without the -dD implicitly added for -g3 the -g3 option can't work
> as documented, in particular record the macros in the debug information. 
> Because they would be irrecoverably lost during the preprocessing phase.

I think there is a bit of misunderstanding.
The question is:
I re-checked and found that not only "gcc -g3"
sets -dD for cpp (which I understand), but also
"cpp -g3" does the same. Raw cpp, not gcc.
Should cpp react on -gX directly, rather than
on an implicitly set -dD?

But:
$ gcc -Wp,-g3 -E -Wp,-P -xc - </dev/null

doesn't produce any output... confused.

$ cpp -g3 -P -xc -g0 - </dev/null

shouldn't produce anyothing, or?