gdb/375: debug problems when there are multiple expansions of same template

[jbuck at synopsys dot com]

>Number:         375
>Category:       gdb
>Synopsis:       debug problems when there are multiple expansions of same template
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Feb 22 12:08:00 PST 2002
>Closed-Date:
>Last-Modified:
>Originator:     Joe Buck
>Release:        5.1.1
>Organization:
>Environment:
sparc-sun-solaris2.7
>Description:
Consider the program in the attachment
below.  Notice that there are two expansions of "func",
based on two values for the template argument.

If a breakpoint is set at line 15, it affects only the first
template expansion: func<5>(sc_uint<5> const&).  There is
no breakpoint in func<6>(sc_uint<6> const&), furthermore
there doesn't appear to be any way of setting such a breakpoint, as gdb doesn't seem to be able to find the
func symbols by name completion as in "break 'fu TAB".

By contrast, a recent version of Sun's dbx debugger understands that there can be a many-to-one mapping of
source lines and names.  Under that debugger, if I set
a breakpoint at line 15 it affects both template expansions,
turning into two breakpoints.  gdb should do this.

It is possible that this is exposing two distinct bugs:
handling multiple template expansions, and C++ name lookup
>How-To-Repeat:
I compiled the attached program with gcc 3.0.3 on Solaris 2.7.
First say "break 15" and run the program to completion.
Observe that there is only one breakpoint, in the first call
to func.
Now try to find a way of setting a breakpoint in the second
function.  Everything I tried fails: gdb can't locate any
symbols named "func", and gdb is convinced that the line
number refers only to the first template expansion.
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
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