Re: [PATCH v6 15/27] compiler: Option to default to hidden symbols

From: Thomas Garnier
Date: Fri Feb 01 2019 - 12:35:15 EST


On Fri, Feb 1, 2019 at 12:24 AM Adrian Hunter <adrian.hunter@xxxxxxxxx> wrote:
>
> On 31/01/19 9:24 PM, Thomas Garnier wrote:
> > Provide an option to default visibility to hidden except for key
> > symbols. This option is disabled by default and will be used by x86_64
> > PIE support to remove errors between compilation units.
> >
> > The default visibility is also enabled for external symbols that are
> > compared as they maybe equals (start/end of sections). In this case,
> > older versions of GCC will remove the comparison if the symbols are
> > hidden. This issue exists at least on gcc 4.9 and before.
>
> What does this mean, if anything, for what/how symbols appear in /proc/kallsyms?

No, they will still appear in kallsyms. Some symbols are not absolute
anymore or moved sections but still present.

--
Thomas