Post GDB 6.2, require new frame code

[Jim Blandy]

Andrew Cagney <cagney@gnu.org> writes:
> GDB's new frame infrastructure was introduced more than a year ago
> (dwarf2-frame added May '03) and then included in the 6.0 and 6.1
> releases.  Since that introduction, we've seen:
> 
> 	alpha ARM AVR CRIS d10v FRV
> 	PA-RISC i386 ia64 m32r m68hcll
> 	m68k m88k mips ppc s390 sh4
> 	sparc vax
> 
> all updated to this new framework.  Unfortunately, though, we're still
> left with a few architectures relying on the old framework.

For concreteness, it looks like those would be:

   h8300 mcore mn10300 ns32k sh64 v850 xstormy16

Supporting the old frame interfaces is a burden, and one that there's
no good reason to carry forever.  But listing things as obsolete in
NEWS isn't a very high-profile step; I think many, many users don't
read NEWS.  For example, remember that old discussion about obsoleting
annotate level 2?

If the intent is to provide some warning, I think it work better to
add something a user would actually see.  For example, if GDB is
configured for an obsolete architecture, it could print a one-line
message at startup, after the copyright notice, saying "Support for
the Intel 4004 will be removed after GDB 6.2; see NEWS."  The NEWS
entry would clarify, saying that it was obsolete only due to a lack of
sustaining maintenance, and that if anyone contributed modernized
code, we'd be happy to continue support for that architecture.

What I'm suggesting is that the intermediate phase between "fully
supported" and "removed" be marked with a visible behavior change in
GDB that users will be likely to notice, without reading NEWS or any
other documentation.