c++/2039: bad code generated for access to unnamed union in base class

[jlemke at itcnet dot de]

>Number:         2039
>Category:       c++
>Synopsis:       bad code generated for access to unnamed union in base class
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          wrong-code
>Submitter-Id:   net
>Arrival-Date:   Tue Feb 20 07:26:01 PST 2001
>Closed-Date:
>Last-Modified:
>Originator:     jlemke@itcnet.de
>Release:        g++-2.95.2
>Organization:
>Environment:
AIX 4.3 (does also appear on Linux egcs-2.91.66)
>Description:
access to an item in an unnamed union of a base class
produces code with wrong addressing. see sample

> g++ -v x.cpp -o x
Reading specs from /usr/local/lib/gcc-lib/powerpc-ibm-aix4.3.2.0/2.95.2/specs
gcc version 2.95.2 19991024 (release)
 /usr/local/lib/gcc-lib/powerpc-ibm-aix4.3.2.0/2.95.2/cpp -lang-c++ -v -D__GNUC_
_=2 -D__GNUG__=2 -D__GNUC_MINOR__=95 -D__cplusplus -D_IBMR2 -D_POWER -D_AIX -D_A
IX32 -D_AIX41 -D_AIX43 -D_LONG_LONG -D_IBMR2 -D_POWER -D_AIX -D_AIX32 -D_AIX41 -
D_AIX43 -D_LONG_LONG -Asystem(unix) -Asystem(aix) -D__EXCEPTIONS -D__CHAR_UNSIGN
ED__ -D_ARCH_COM x.cpp x.ii
GNU CPP version 2.95.2 19991024 (release)
#include "..." search starts here:
#include <...> search starts here:
 /usr/local/lib/gcc-lib/powerpc-ibm-aix4.3.2.0/2.95.2/../../../../include/g++-3
 /usr/local/include
 /usr/local/lib/gcc-lib/powerpc-ibm-aix4.3.2.0/2.95.2/../../../../powerpc-ibm-ai
x4.3.2.0/include
 /usr/local/lib/gcc-lib/powerpc-ibm-aix4.3.2.0/2.95.2/include
 /usr/include
End of search list.
The following default directories have been omitted from the search path:
End of omitted list.
 /usr/local/lib/gcc-lib/powerpc-ibm-aix4.3.2.0/2.95.2/cc1plus x.ii -quiet -dumpb
ase x.cc -version -o x.s
GNU C++ version 2.95.2 19991024 (release) (powerpc-ibm-aix4.3.2.0) compiled by G
NU C version 2.95.2 19991024 (release).
 as -u -mcom -o x.o x.s
 /usr/local/lib/gcc-lib/powerpc-ibm-aix4.3.2.0/2.95.2/collect2 -bpT:0x10000000 -
bpD:0x20000000 -btextro -bnodelcsect -o x /lib/crt0.o -L/usr/local/lib/gcc-lib/p
owerpc-ibm-aix4.3.2.0/2.95.2 -L/usr/local/lib x.o -lstdc++ -lm /usr/local/lib/gc
c-lib/powerpc-ibm-aix4.3.2.0/2.95.2/libgcc.a -lc /usr/local/lib/gcc-lib/powerpc-
ibm-aix4.3.2.0/2.95.2/libgcc.a

> x
f1: ia1=11111111
f1: ia2=22222222
f2: ia1=44444444
f2: ia2=22222222
>How-To-Repeat:

>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
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Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename="x.cpp"

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