On Tue, Jan 13, 2015 at 04:54:32AM -0800, H.J. Lu wrote:
> On Mon, Jan 12, 2015 at 03:04:20PM -0700, Jeff Law wrote:
> > On 01/12/15 14:51, Magnus Granberg wrote:
> > >måndag 12 januari 2015 12.11.17 skrev H.J. Lu:
> > >>On Mon, Jan 12, 2015 at 12:03 PM, Jeff Law <l...@redhat.com> wrote:
> > >>>On 01/12/15 12:59, H.J. Lu wrote:
> > >>>>I don't know if -pg will work PIE on any targets. For Linux/x86
> > >>>>the choices of crt1.o are
> > >>>>
> > >>>>%{!shared: %{pg|p|profile:gcrt1.o%s;pie:Scrt1.o%s;:crt1.o%s}}
> > >>>>
> > >>>>-shared, -pg and -pie are mutually exclusive. Those crt1 files are
> > >>>>only crt1 files provided by glibc. You can't even try -pg -pie on
> > >>>>Linux without changing glibc.
> > >>>
> > >>>You're totally missing the point. What I care about is *why*.
> > >>>
> > >With -pg it use gcrt1.o object file and that file is not compile with
> > >-fPIC.
> > >When you build a shared lib on x86_64 all the objects files need to be
> > >buiit
> > >with -fPIC else you get a error like that one abow and it is the same
> > >problems
> > >when you build bin with -fPIE and linke with -pie.
> > >Glibc do not provide one that is compile with -fPIC
> > Is there some reason why glibc could not provide gcrt1.o compiled with
> > -fPIC?
> >
> >
>
> Here is a patch to check if -pg is available. If -pg doesn't link,
> profiling isn't available. OK for trunk?
>
> Thanks.
>
>
> H.J.
> ---
> gcc/testsuite/lib/target-supports.exp | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/gcc/testsuite/lib/target-supports.exp
> b/gcc/testsuite/lib/target-supports.exp
> index 0ac9646..7c09399 100644
> --- a/gcc/testsuite/lib/target-supports.exp
> +++ b/gcc/testsuite/lib/target-supports.exp
> @@ -546,6 +546,12 @@ proc check_profiling_available { test_what } {
> set profiling_available_saved 0
> } else {
> set profiling_available_saved 1
> + if { [check_no_compiler_messages_nocache profiling executable {
> + int main() { return 0; } } "-pg"] } {
> + set profiling_available_saved 1
> + } else {
> + set profiling_available_saved 0
> + }
> }
> }
>
Here is the ChangeLog entry.
2015-01-13 H.J. Lu <hongjiu...@intel.com>
* lib/target-supports.exp (check_profiling_available): Check if
-pg links.
H.J.
