kumquat-buildroot/package/binutils
Alexey Brodkin 5642c89e70 binutils: fix building perf on ARC
It turned out one of the previous fixes (required to build Linux
kernel)
------------------>8-------------------
ARC Binutils: a65b844aed
Buildroot: http://git.buildroot.net/buildroot/commit/?id=2d4e2e238a0ea9395152ae71d882d79b1f35094c
------------------>8-------------------
broke building of some other software packages.

In particular perf built for ARCv2 had corrupted .plt entries that lead
to immediate crash on perf execution.

That's an example of normal .plt entries:
------------------>8-------------------
< 1-st PLT entry >:
   12c24:    30 27 8c 7f 0d 00 74 95    ld         r12,[pcl,0x000d9574]
   12c2c:    21 20 00 03                j.d        [r12]
   12c30:    0a 24 c0 1f                mov        r12,pcl

< 2-nd PLT entry >:
   12c34:    30 27 8c 7f 0d 00 68 95    ld         r12,[pcl,0x000d9568]
   12c3c:    21 20 00 03                j.d        [r12]
   12c40:    0a 24 c0 1f                mov        r12,pcl
------------------>8-------------------
Note right after jump in its delay-slot r12 gets set with current value
of program counter. This is required for the first symbol resolution,
see implementation of _dl_linux_resolve here:
http://git.uclibc.org/uClibc/tree/ldso/ldso/arc/resolve.S#n46

And that's what we got in .plt after mentioned fixes:
------------------>8-------------------
< 1-st PLT entry>:
   13384:    30 27 8c 7f 0f 00 84 75     ld         r12,[pcl,0x000f7584]
   1338c:    21 20 00 03                 j.d        [r12]

< 2-nd PLT entry>:
   13390:    30 27 8c 7f 0f 00 78 75     ld         r12,[pcl,0x000f7578]
   13398:    21 20 00 03                 j.d        [r12]
------------------>8-------------------

Note r12 setup is missing.

That happened because linker thought the size of PLT entry is 12 bytes
(which is exactly the size of PLT entry for ARCv1, read ARC750/770)
while for ARCv2 PLT entry is 16-bytes long. And erroneously trailing 4
bytes were truncated.

Current commit fixes this misbehavior and PLT gets generated properly
again.

Now we have a fix for that issue, see
5df50c6108

This fix is in arc-2.23-dev branch and will be a part of the next
release of ARC tools, so then this patch must be removed from buildroot.

Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
2015-10-17 16:16:53 +02:00
..
2.23.2
2.24 binutils: backport auto-litpools xtensa gas option 2015-10-04 17:27:27 +01:00
2.25.1 binutils: backport auto-litpools xtensa gas option 2015-10-04 17:27:27 +01:00
arc-2015.06 binutils: fix building perf on ARC 2015-10-17 16:16:53 +02:00
binutils.hash
binutils.mk binutils: remove unnecessary host-texinfo dependency 2015-09-20 14:57:02 +02:00
Config.in
Config.in.host arch: add support for mips32r6 and mips64r6 variants 2015-10-12 21:33:56 +02:00