[Bug debug/48459] [4.6/4.7 Regression] avr: Assertion failure with -gdwarf-2

[anitha.boyapati at atmel dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48459

--- Comment #18 from Anitha Boyapati <anitha.boyapati at atmel dot com> 2011-06-14 07:00:45 UTC ---
(In reply to comment #17)
> Created attachment 24512 [details]
> loosen constraints on register elimination
> 
> This seems to fix the problem.  At least for this small test case.

I think there are 2 issues here. The first issue deals with avr-gcc which was
built without dwarf2 support. The second issue (comment #1 onwards) deals with
avr build errors. Maybe we should separate them.


> A full build for AVR fails, but that seems to be related to other
> open bugs.

Please let me know if any other known bugs exist with regarding to build
failure. AFAIK, there are some open PRs for emitting CFI information but not
for build failures (Bug #44643 is fixed)

But the current 4.6.0 build is without CFI support, which is possible as CFI is
optional. As far as I have analyzed, AVR build with DWARF2 support fails with
the reasons discussed in comment #3 (and later on). All the changes were made
in 4.6.0 release. Since the build is known to pass in 4.5.x release, this is a
regression. And I think we need to address these issues as part of this bug.