https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62281
Bug ID: 62281
Summary: gcc doesn't conform to Solaris 32-bit ABI by expecting
16-byte stack alignment
Product: gcc
Version: 4.9.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: justin.carveley at oracle dot com
Created attachment 33400
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=33400&action=edit
Example 2: SSE vector load causes SEGV on callback from Xt timer
This is essentially a resubmission of bug 47842 "gcc forces 16-byte stack
alignment on Solaris i386, when SYSV requires word alignment".
As described in the above bug, changes to gcc for Linux x86 cause generated
code to assume a 16-byte preferred and incoming stack alignment. However, this
behaviour does not conform to the Solaris x86 (32-bit) ABI, which is still
based on http://www.sco.com/developers/devspecs/abi386-4.pdf and only specifies
that the stack be 32-bit word aligned.
PR 47842 was closed due to a lack of test cases. Here, therefore, are two test
cases that demonstrate the problem:
Example 1: Mixing 32-bit modules compiled with the Solaris Studio 12.3 and gcc:
Using:
- Solaris Studio compiler from
http://www.oracle.com/technetwork/server-storage/solarisstudio/downloads/index-jsp-141149.html
- gcc 4.8.0 (stable) or gcc 4.9.0 (unstable) package from
http://www.opencsw.org/
or gcc 4.9.1 built from tarball
Files: x.c, y.c, build
Result:
GNU gdb (GDB) 7.6
Copyright (C) 2013 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
This GDB was configured as "i386-pc-solaris2.10".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>...
Reading symbols from /export/home/justin/tmp/xy...done.
(gdb) r
Starting program: /export/home/justin/tmp/xy
Program received signal SIGSEGV, Segmentation fault.
0x080509db in _mm_set_epi8 (__q00=1 '\001', __q01=1 '\001', __q02=1 '\001',
__q03=1 '\001', __q04=1 '\001', __q05=1 '\001', __q06=1 '\001',
__q07=1 '\001', __q08=1 '\001', __q09=1 '\001', __q10=1 '\001',
__q11=1 '\001', __q12=1 '\001', __q13=1 '\001', __q14=1 '\001',
__q15=1 '\001')
at
/opt/tarantella/lib/gcc/i386-pc-solaris2.10/4.8.0/include/emmintrin.h:602
602 return __extension__ (__m128i)(__v16qi){
(gdb) where
#0 0x080509db in _mm_set_epi8 (__q00=1 '\001', __q01=1 '\001',
__q02=1 '\001', __q03=1 '\001', __q04=1 '\001', __q05=1 '\001',
__q06=1 '\001', __q07=1 '\001', __q08=1 '\001', __q09=1 '\001',
__q10=1 '\001', __q11=1 '\001', __q12=1 '\001', __q13=1 '\001',
__q14=1 '\001', __q15=1 '\001')
at
/opt/tarantella/lib/gcc/i386-pc-solaris2.10/4.8.0/include/emmintrin.h:602
#1 _mm_set1_epi8 (__A=1 '\001')
at
/opt/tarantella/lib/gcc/i386-pc-solaris2.10/4.8.0/include/emmintrin.h:637
#2 test_sse () at x.c:5
#3 0x08050a1b in main (argc=1, argv=0x8047d74) at y.c:5
(gdb)
Example 2: libXt timer callback
Using:
- gcc 4.8.0 (stable) or gcc 4.9.0 (unstable) packages from
http://www.opencsw.org/
- or gcc 4.9.1 from tarball
File: xt.c
Result:
The stack becomes only 4-byte aligned on callback from Xt.
GNU gdb (GDB) 7.6
Copyright (C) 2013 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
This GDB was configured as "i386-pc-solaris2.10".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>...
Reading symbols from /export/home/justin/tmp/xt...done.
(gdb) r
Starting program: /export/home/justin/tmp/xt
Program received signal SIGSEGV, Segmentation fault.
0x08050e97 in _mm_set_epi8 (__q00=1 '\001', __q01=1 '\001', __q02=1 '\001',
__q03=1 '\001', __q04=1 '\001', __q05=1 '\001', __q06=1 '\001',
__q07=1 '\001', __q08=1 '\001', __q09=1 '\001', __q10=1 '\001',
__q11=1 '\001', __q12=1 '\001', __q13=1 '\001', __q14=1 '\001',
__q
