Re: Huge Increase in Unstripped Executable Size G++ 2.95 to 3.2

[Richard Henderson <rth at redhat dot com>]

On Fri, Feb 28, 2003 at 03:55:59PM -0600, snyder wrote:
> I didn't get comments on the last version of the
> -feliminate-unused-dwarf2-types patch that i posted.

Sorry for not following up.

> This patch makes no changes in the gcc testsuite results, even
> if i change the default for the switch to 1.  It causes one failure
> in the gdb test suite, where the test was asking for information
> about a type that was declared but not used.

If we can come to an arrangement with the gdb folk regarding
their testsuite, I think it would be useful to have this 
default to 1.

> There were a couple comments about the option name: that maybe
> it should be something like -feliminate-unused-debug-types,

I do think this sounds better.

> A caveat is that this may not interact well with the mechanism for
> dwarf2 duplicate removal.  As i understand how that works, it relies
> on a given header file generating the same debugging information,
> regardless of what compilation unit it is included into.  This
> patch will invalidate that assumption.

Well, that could be delt with, possibly by turning off
-feliminate-unused-debug-types when -feliminate-dwarf2-dups
is enabled.  Or possibly by arranging for stuff mentioned
from non-default dwarf2 sections to be marked.

I'm not really worried about this though, since I'm not really
a fan of our current duplicate header removal code though;
compare-by-hash is fundamentally flawed.

I'll bootstrap your patch, change the name of the option, and
apply it as-is, i.e. disabled by default.  We can address the
other issues raised as a followup.


r~