c++/2892: array addresses corrupted when using template classes

[ianw at sgi dot com]

>Number:         2892
>Category:       c++
>Synopsis:       array addresses corrupted when using template classes
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon May 21 15:56:02 PDT 2001
>Closed-Date:
>Last-Modified:
>Originator:     Ian Williams
>Release:        gcc version 2.96 20000731 (Red Hat Linux 7.1 2.96-81)
>Organization:
>Environment:
RedHat7.1 i386
>Description:
Array addresses passed into a template class seem to get
corrupted through the call.

The attached program shows the issue.
>How-To-Repeat:
Compile the attached program and run it. It will print out
the contents of several arrays through the call to the
template class.

The ouput should look something like:

./test
Input = 1, -1, 1
item = 2.17777, -1.99912, -1.99909
mBuffer[0] = 2.17777, -1.99912, -1.99909, 
Output = 2.17777, -1.99912, -1.99909
Input = 1, 1, -1
item = 2.17777, -1.99912, -1.99909
mBuffer[1] = 2.17777, -1.99912, -1.99909, 
Output = 2.17777, -1.99912, -1.99909
Input = 1, 1, 1
item = 2.17777, -1.99912, -1.99909
mBuffer[2] = 2.17777, -1.99912, -1.99909, 
Output = 2.17777, -1.99912, -1.99909
Input = 1, -1, 1
item = 2.17777, -1.99912, -1.99909
mBuffer[3] = 2.17777, -1.99912, -1.99909, 
Output = 2.17777, -1.99912, -1.99909

The contents of the 'input' array should be the same as
'item', 'mbuffer' and 'output', however, they aren't and
it appears as though the address gets mangled through the 
call. 

The same problem occures if the class is instanced to any
type of 'int', 'float' or 'double' arrays.
>Fix:

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