Solaris 2.6 panic when debugging with gdb
Description of problem:
Running gdb with a breakpoint that gets hit triggers a panic:
```
non parity synchronous error ctx=fa va=ef7d97c pa=c1a47c
```

One time I got of the following messages as well
```
processor level 12 onboard interrupt not serviced
processor level 12 onboard interrupt not serviced
...
```
Steps to reproduce:
1. Install Solaris 2.6 using https://learn.adafruit.com/build-your-own-sparc-with-qemu-and-solaris?view=all
2. Install https://archive.org/details/sun26gnu
3. Install http://download.nust.na/pub3/solaris/sunfreeware/pub/unixpackages/sparc/5.6/gdb-6.8-sol26-sparc-local.gz
4. Install http://download.nust.na/pub3/solaris/sunfreeware/pub/unixpackages/sparc/5.6/gcc-2.95.3-sol26-sparc-local.gz
5. Build a simple hello world program with debugging information
6.
```
gdb ./hello
(gdb) break main
(gdb) run
```