MySQL Bugs: #26742: mysql_client_test fails on 32-bit linux with gcc 4.1.1

Bug #26742	mysql_client_test fails on 32-bit linux with gcc 4.1.1
Submitted:	1 Mar 2007 7:19	Modified:	26 Jun 2007 18:36
Reporter:	Giuseppe Maxia	Email Updates:
Status:	Can't repeat	Impact on me:	None
Category:	MySQL Server: Tests	Severity:	S3 (Non-critical)
Version:	5.0.37 Community, 5.0.40	OS:	Linux (Linux)
Assigned to:	Gleb Shchepa	CPU Architecture:	Any
Tags:	build, embedded, gcc, linux.test

Description:
I tested the 5.0 community tree in my machines, and I got two failures  (mysql_client_test and func_group) in 2 Linux boxes, running Fedora Core 6 and Ubuntu 6.0.10

I was puzzled, because the pushbuild tree is green
https://intranet.mysql.com/~knielsen/pb/showdir.pl?dir=mysql-5.0-community

So I investigated more.
1) the failure happens only in 32-bit machines
2) building with "debug" enabled passes the tests
3) pushbuild green boxes are all 64 bits, except one. The 32 bit box was running the "gcov" build (https://intranet.mysql.com/~knielsen/pb/plat-queue.pl?plat=rh-x86-32)
4) I rebuilt on my 2 32-bit Linux machines with gcov enabled, and it passed the tests.
5) I tested on a few 32-bit Linux machines in QA, and the tests passed. The noticeable difference between those boxes and mine is the CPU class and the compiler version. It's gcc 4.1.1 in my machines, 4.0.3 on QA machines
(see below) 

CPU comparison
(where it fails: dual proc)
Linux fedora6 2.6.19-1.2911.fc6 #1 SMP Sat Feb 10 15:03:33 EST 2007 i686 i686 i386 GNU/Linux
processor       : 1
vendor_id       : GenuineIntel
cpu family      : 6
model           : 15
model name      : Intel(R) Core(TM)2 CPU          6400  @ 2.13GHz
stepping        : 6
cpu MHz         : 2131.283

(where it fails: 1 proc)
Linux ubuntu6 2.6.17-10-generic #2 SMP Tue Dec 5 22:28:26 UTC 2006 i686 GNU/Linux
processor       : 0
vendor_id       : GenuineIntel
cpu family      : 6
model           : 15
model name      : Intel(R) Core(TM)2 CPU         T7200  @ 2.00GHz
stepping        : 6
cpu MHz         : 1211.443
cache size      : 4096 KB

(where it passes: quad proc)
Linux qa-suse9-x86 2.6.11.4-21.12-bigsmp #1 SMP Wed May 10 09:38:20 UTC 2006 i686 i686 i386 GNU/Linux
processor       : 3
vendor_id       : GenuineIntel
cpu family      : 15
model           : 3
model name      : Intel(R) Xeon(TM) CPU 3.60GHz
stepping        : 4
cpu MHz         : 3591.842
cache size      : 1024 KB

(where it passes: quad proc)
Linux qa-srv-b 2.6.5-7.97-smp #1 SMP Fri Jul 2 14:21:59 UTC 2004 i686 i686 i386 GNU/Linux
processor       : 3
vendor_id       : GenuineIntel
cpu family      : 15
model           : 4
model name      : Intel(R) Xeon(TM) CPU 3.00GHz
stepping        : 1
cpu MHz         : 3002.320
cache size      : 1024 KB

How to repeat:
Take a 32-bit Linux box 
compile with BUILD/compile-pentium-max and run the test suite

repeat with BUILD/compile-pentium-debug

Tested again on the same machines where it was failing, but a different compiler.
Using gcc 4.0.4 the test passes, while using 4.1.1 or later, it fails.

This is now failing in 5.0.40 main i386 release builds

Can't repeat these fails on 32bit Linux build of 5.0.40 and 5.0-bk with GCC 4.1.1.