Subject: flag traps in ld.so
To: None <port-pc532@NetBSD.ORG>
From: Ian Dall <dall@hfrd.dsto.gov.au>
List: port-pc532
Date: 09/27/1995 09:12:27
I have been trying to figure out why lites can't run dynamically linked
netbsd532 binaries.

It turns out that ld.so generates a "flag" trap by setting the flag
bit in the psr and then immediately executing the "flag" instruction.
My guess is that this is to allow a debugger to gain control and do
something with the symbols in the library.

I made lites treat a flag trap as a SIGFPE with a code to indicate it
is really a flag trap. Perhaps this wasn't the wisest decision, but there
is no SIGFLAG! So, in netbsd, how is a flag trap handled?

Ian