[Bug gcov-profile/103666] [11/12 Regression] compiling single-file programs with -fprofile-generate no longer leads to intended results since r11-627-g1dedc12d186a1108

["rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103666

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|---                         |WONTFIX
            Summary|[11/12 Regression]          |[11/12 Regression]
                   |compiling single-file       |compiling single-file
                   |preprocessed programs with  |programs with
                   |-fprofile-generate no       |-fprofile-generate no
                   |longer leads to intended    |longer leads to intended
                   |results since               |results since
                   |r11-627-g1dedc12d186a1108   |r11-627-g1dedc12d186a1108

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
that's because the explicitely named linker output in the -fprofile-use case. 
A fix might be to separate compile and link step.  I don't think there's
anything special about using preprocessed source:

> cat t.c
int main(){}
> ./xgcc -B. t.c -fprofile-generate
> ./a.out 
> ./xgcc -B. t.c -fprofile-use -o a.out-use
t.c: In function 'main':
t.c:1:1: warning: '/tmp/obj/gcc/a.out-use-t.gcda' profile count data file not
found [-Wmissing-profile]
    1 | int main(){}
      | ^~~
> ls *.gcda
a-t.gcda

I'd declare this as WONTFIX.  I've adjusted the C++ tester for tramp3d to use
an
explicit -dumpbase