If you use the HP Precision Architecture (HP-9000/7xx and HP-9000/8xx) and you want to use debugging, you'll need to use the GNU assembler, GAS (version 2.3 or later). If you build from source, you must tell the configure program that you are using GAS or you won't get debugging support. A non-standard debug format is used, since until recently HP considered their debug format a trade secret. Thanks to the work of lots of good folks both inside and outside HP, the company has seen the error of its ways and has now released the required information. The team at the University of Utah that did the gcc port now has code that understands the native HP format.
Some enhancements for the HP that haven't been integrated back into the official GCC are available from the University of Utah, site jaguar.cs.utah.edu. You can retrieve sources and prebuilt binaries for GCC, GDB, binutils,and libg++; see the directory `/dist'.
The libg++ version is actually the same as the FSF 2.6. The Utah version of GDB can now understand both the GCC and HP C compiler debug formats, so it is no longer necessary to have two different GDB versions.
I recommend that HP users use the Utah versions of the tools (see above), though at this point the standard FSF versions will work well.
HP GNU users can also find useful stuff on the site geod.emr.ca in the `/pub/UNIX/GNU-HP' directory.
Jeff Law is leaving the University of Utah, so the Utah prebuilt binaries may be discontinued.