[Bug c/30796] New: gcc 4.2.0 misscompiles glibc on linux-ppc 32bit

[Bug c/30796] New: gcc 4.2.0 misscompiles glibc on linux-ppc 32bit

[arekm at pld-linux dot org]

Hello,

I'm getting bad results on linux-ppc platform. Building glibc 2.5 or glibc HEAD
using recent gcc snapshot (20070207) on linux ppc 32bit causes rpcgen binary
(built and later used in rest of glibc build process) to segfault. On x86_64,
x86 there is no problem.

In my case:
gcc-4.2.0-0.20070207.1.ppc (version from ~ October 2006 was afaik OK)
binutils-2.17.50.0.12-1.ppc (tried 2.17.50.0.5, 0.7, 0.11, too)

Trying to reproduce under gdb:

[builder2@forge sunrpc]$ CPP='gcc -E -x c-header' 
gdb --args /home/users/builder2/libc/build/elf/ld.so.1 --library-path
/home/users/builder2/libc/build:/home/users/builder2/libc/build/math:/home/users/builder2/libc/build/elf:/home/users/builder2/libc/build/dlfcn:/home/users/builder2/libc/build/nss:/home/users/builder2/libc/build/nis:/home/users/builder2/libc/build/rt:/home/users/builder2/libc/build/resolv:/home/users/builder2/libc/build/crypt:/home/users/builder2/libc/build/nptl
/home/users/builder2/libc/build/sunrpc/rpcgen -Y ../scripts -c 
rpcsvc/bootparam_prot.x -o
/home/users/builder2/libc/build/sunrpc/xbootparam_prot.T
GNU gdb 6.6
Copyright (C) 2006 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "ppc-pld-linux"...
(no debugging symbols found)
Using host libthread_db library "/lib/libthread_db.so.1".
(gdb) r
Starting 
program: /home/users/builder2/libc/build/elf/ld.so.1 --library-path
/home/users/builder2/libc/build:/home/users/builder2/libc/build/math:/home/users/builder2/libc/build/elf:/home/users/builder2/libc/build/dlfcn:/home/users/builder2/libc/build/nss:/home/users/builder2/libc/build/nis:/home/users/builder2/libc/build/rt:/home/users/builder2/libc/build/resolv:/home/users/builder2/libc/build/crypt:/home/users/builder2/libc/build/nptl
/home/users/builder2/libc/build/sunrpc/rpcgen -Y ../scripts -c 
rpcsvc/bootparam_prot.x -o
/home/users/builder2/libc/build/sunrpc/xbootparam_prot.T
(no debugging symbols found)

Program received signal SIGSEGV, Segmentation fault.
0x0801778c in _start ()
(gdb) bt
#0  0x0801778c in _start ()
#1  0x08017778 in _start ()
Cannot access memory at address 0x0
(gdb) quit

It seem that similar errors were visible in older gcc versions (there are
bugreports in bugzilla). Looks like the problem is back again.


-- 
           Summary: gcc 4.2.0 misscompiles glibc on linux-ppc 32bit
           Product: gcc
           Version: 4.2.0
            Status: UNCONFIRMED
          Severity: major
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: arekm at pld-linux dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30796

[Bug c/30796] gcc 4.2.0 misscompiles glibc on linux-ppc 32bit

[pluto at agmk dot net]

------- Comment #1 from pluto at agmk dot net  2007-02-14 19:26 -------
it alse miscompiles glibc at:

-O1 -fno-strict-aliasing -fsigned-char -fwrapv -g2 -gdwarf-2 -mnew-mnemonics
-mlong-double-128  -fomit-frame-pointer

looks like a heavy damage :/


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30796

[Bug c/30796] gcc 4.2.0 misscompiles glibc on linux-ppc 32bit

[pinskia at gcc dot gnu dot org]

------- Comment #2 from pinskia at gcc dot gnu dot org  2007-02-14 19:31 -------
Try adding -fno-section-anchors if that works, then this is a dup of bug 29943.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30796

[Bug c/30796] gcc 4.2.0 misscompiles glibc on linux-ppc 32bit

[arekm at pld-linux dot org]

------- Comment #3 from arekm at pld-linux dot org  2007-02-14 20:25 -------
pluto confirms that's a duplicate of 29943

*** This bug has been marked as a duplicate of 29943 ***


-- 

arekm at pld-linux dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |DUPLICATE


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30796