This is the mail archive of the
mailing list for the glibc project.
PT_NOTE alignment, NT_GNU_PROPERTY_TYPE_0, glibc and gold (was: Re: [PATCH] Document GNU_PROPERTY_X86_ISA_1_[USED|NEEDED])
- From: Florian Weimer <fweimer at redhat dot com>
- To: "H.J. Lu" <hjl dot tools at gmail dot com>
- Cc: x86-64-abi at googlegroups dot com, Binutils <binutils at sourceware dot org>, GNU C Library <libc-alpha at sourceware dot org>
- Date: Thu, 16 Aug 2018 15:00:03 +0200
- Subject: PT_NOTE alignment, NT_GNU_PROPERTY_TYPE_0, glibc and gold (was: Re: [PATCH] Document GNU_PROPERTY_X86_ISA_1_[USED|NEEDED])
- References: <CAMe9rOrrayKnc_cPm4SmnDnUGLbBUmOYMBTMOM8KLAHVmb=rUQ@mail.gmail.com>
On 08/07/2018 10:41 PM, H.J. Lu wrote:
The .note.gnu.property section with NT_GNU_PROPERTY_TYPE_0 has been
added to Linux Extensions to gABI:
GNU_PROPERTY_X86_ISA_1_USED and GNU_PROPERTY_X86_ISA_1_NEEDED are
processor-specific program property types for i386 and x86-64.
The specification is incomplete as far as alignment matters are concerned.
Is the link editor supposed to maintain separate segments for notes with
different alignments? Or is it possible to merge the notes into a
single segment, potentially after adjusting alignment?
Is the link editor *required* to produce 8-byte alignment for notes in
Currently, we do not have agreement between binutils (particularly gold)
and the glibc dynamic loader when it comes to alignment of PT_NOTE
segments. glibc will disregard property notes in ELFCLASS64 objects
which have 4-byte alignment, but gold produces such notes. This needs
to be fixed.