c++/443: Enabling optimization causes a link failure

[sedwards@alumni.caltech.edu]

>Number:         443
>Category:       c++
>Synopsis:       Enabling optimization causes a link failure
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          wrong-code
>Submitter-Id:   net
>Arrival-Date:   Thu Aug 03 14:46:01 PDT 2000
>Closed-Date:
>Last-Modified:
>Originator:     sedwards@alumni.caltech.edu
>Release:        unknown-1.0
>Organization:
>Environment:
Observed under egcs-2.91.66 on i386-redhat-linux and
under 2.95.2 on sparc-SUN-SOLARIS2.5.1
>Description:
Small program (a single file, attached) compiles and
links correctly without -O flag, but fails to link
(unresolved symbol) with -O option.  Optimizer appears
to prevent code for a virtual function defined within
a class within a method from being generated.

% /bar/gcc-2.95.2/bin/g++ -O g++bug.cxx 
Undefined                       first referenced
 symbol                             in file
bar__Q33Baz9q__3Baz.0_3BarRi.9      /var/tmp/ccf8wr87.o
ld: fatal: Symbol referencing errors. No output written to a.out
collect2: ld returned 1 exit status
% /bar/gcc-2.95.2/bin/g++  g++bug.cxx 
% # Successful
>How-To-Repeat:
Try to compile this program with -O flag.  Linking should
fail.
>Fix:
Moving definition of class Bar outside scope of Baz::q()
makes it compile, but this should not be necessary.
>Release-Note:
>Audit-Trail:
>Unformatted:
----gnatsweb-attachment----
Content-Type: application/x-unknown-content-type-cppfile; name="g++bug.cxx"
Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename="g++bug.cxx"

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