On Tue, Oct 06, 2020 at 04:46:24PM -0600, Jeff Law wrote:
On 9/30/20 3:50 AM, Jan Kratochvil wrote:
> On Wed, 30 Sep 2020 01:31:29 +0200, Jeff Law wrote:
>> But the GCC community
>> doesn't really test that option and it's known to be broken with LTO.
> I haven't seen any GCC PR for -fdebug-types-section being broken with LTO.
I'm not aware of one either. But as Jakub has previously pointed out
debug-types-section is disabled when LTO is enabled. I don't know the
details of why that is done.
> Could you suggest what is wrong on -fdebug-types-section?
Your best bet is to discuss with Jakub and perhaps Jason. They're far
more familiar with the debuginfo generation than I am.
It didn't used to work with LTO, but some patches have been backported
so it at least is passed through now without crashing. There are
however still various bugs in the implementation:
Excess debug info -fdebug-types-section
-fdebug-types-section drops DW_AT_object_pointer
gcc drops top-level dies with -fdebug-types-section
Fission + type units + compression are suboptimal