[Bug target/65886] [5/6 Regression] Copy reloc in PIE incompatible with DSO created by -Wl,-Bsymbolic

["hjl.tools at gmail dot com" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65886

--- Comment #10 from H.J. Lu <hjl.tools at gmail dot com> ---
(In reply to Thiago Macieira from comment #7)
> (In reply to H.J. Lu from comment #4)
> > (In reply to Thiago Macieira from comment #3)
> > > Thanks H.J.!
> > > 
> > > Can I ask that -fsymbolic be the default? Otherwise, code with -fPIE MUST
> > > add -fsymbolic in GCC 5+, but can't add it prior because the option didn't
> > > exist. Please leave that for a release or two so that we can adapt
> > 
> > Linux kernel has things like
> > 
> > M16_CFLAGS	 := $(call cc-option, -m16, $(CODE16GCC_CFLAGS))
> > 
> > It adds -m16 only if it exits. Why can't KDE do something like this?
> > There are many ways to achieve it and it works with all compilers.
> 
> We can. The problem is not the ability, it's the need to do it.

Now, you have a need :-).

> No buildsystem currently has support for -fsymbolic, since it doesn't exist
> yet. However, the lack of such option will produce subtle bugs. I'm asking
> for a grace period until the changes propagate.
> 

I don't think GCC default should cater shared libraries which
aren't psABI compliant.  It is the risk you take when using a
non-psABI compliant library.
>From gcc-bugs-return-484644-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org Sat Apr 25 17:41:39 2015
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From: "frankhb1989 at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/65890] New: [C++03]sizeof(qualified-id) accepted when the operand denotes a non-static member
Date: Sat, 25 Apr 2015 17:41:00 -0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?ide890

            Bug ID: 65890
           Summary: [C++03]sizeof(qualified-id) accepted when the operand
                    denotes a non-static member
           Product: gcc
           Version: 4.9.1
            Status: UNCONFIRMED
          Severity: minor
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: frankhb1989 at gmail dot com
  Target Milestone: ---

Case:

struct Tag { int m; };

int main()
{
        sizeof(&(Tag::m));
}

According to ISO C++03 5.1/10, this is not well-formed. (But C++11 should
work.) However, G++ 4.9.1 wrongly accepted it even with -std=c++03
-pedantic-errors.
(I have no GCC 5 distro so have not tested it.)