https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116478
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |hubicka at gcc dot gnu.org
Last reconfirmed| |2024-08-25
Component|lto |ipa
Status|UNCONFIRMED |NEW
Keywords| |diagnostic, lto, wrong-code
Ever confirmed|0 |1
--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
We emit the diagnostic from both i386_pe_assemble_visibility and
default_assemble_visibility (if !HAVE_GAS_HIDDEN).
I suspect that what happens is that LTO demotes 'a' to be local thus
'default' now has an effect.
Testing on x86-64 with -flto-partition=1to1 shows
a/0 (a)
Type: function definition analyzed
Visibility: force_output semantic_interposition no_reorder
prevailing_def_ironly
note the missing externally_visible. It's LTRANS unit then has
a/0 (a)
Type: function definition analyzed
Visibility: used_from_other_partition force_output no_reorder
prevailing_def_ironly public visibility_specified visibility:hidden
and we seem to ignore the 'default' visibility attribute on it. I do not
have any access to a mingw toolchain to see how we arrive at a diagnostic
there but adding -fdump-ipa-all-details -save-temps should get you
.000i.graph and 081i.whole-program dumps you can cross-check this against
the above.
I think the desired behavior (on x86-64 as well) is to have 'a' have
default visibility in the output, not hidden as it currently happens on
x86-64-linux.
When processing a visibility attribute we adjust DECL_VISIBILITY and
DECL_VISIBILITY_SPECIFIED but we also add the attribute because
/* Go ahead and attach the attribute to the node as well. This is needed
so we can determine whether we have VISIBILITY_DEFAULT because the
visibility was not specified, or because it was explicitly overridden
from the containing scope. */
(it seems that DECL_VISIBILITY_SPECIFIED could be used for this)
Honza?
