Placement new destructor call optimized out

[Jeff Curless]

We have a template class that we are using with placement new. Code works fine in g++ (Ubuntu 4.8.4-2ubuntu1~14.04.1) 4.8.4,
however in g++ (Ubuntu 5.3.1-14ubuntu2) 5.3.1 20160413, the destructor call is optimized out, even though we explicitly call it.

I have attached sample code (reduced down from our project) to show the issue. If we add a NON-POD data type, everything works
fine... this however is not an option for our project, as in our environment this is normally a packed class, though the example fails
either way.

This works:

g++ -O0 -g -ggdb test.cpp -o test0
./test0
Before:000102030405060708090a0b0c0d0e0f10111213
After :0000000000000000000000000000000000000000

These do not:

g++ -O1 -g -ggdb test.cpp -o test1
g++ -O2 -g -ggdb test.cpp -o test2
g++ -O3 -g -ggdb test.cpp -o test3
./test1
Before:000102030405060708090a0b0c0d0e0f10111213
After :000102030405060708090a0b0c0d0e0f10111213

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Matthias Klose (doko)]

closing as invalid.