RFH: PR 44645 - missing debug info for C++ pointer types

[Jonathan Wakely]

Could someone more familiar with dwarf2out.c take a look at PR 44645?
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44645

It is a fairly problematic regression in C++ debug info, which causes
errors in the python pretty printers for libstdc++ associative
contaienrs (map, set etc.) and has several duplicate PRs now.

As Tom Tromey originally identified, the DIE for some pointer types is
missing DW_AT_type, which makes GDB think it's dealing with a void*
not the actual pointer type, and that prevents dereferencing pointers
while debugging.

I've tried to find a problem in dwarf2out.c on the 4.5 branch and
compared it with the versions on the 4.4 branch and trunk (which don't
have the bug) but I'm stumped.

Any pointers or help would be much appreciated.

Jonathan