On Wed, Apr 03, 2024 at 11:18:01AM -0400, Jason Merrill wrote: > On 4/2/24 20:57, Nathaniel Shead wrote: > > On Tue, Apr 02, 2024 at 01:18:17PM -0400, Jason Merrill wrote: > > > On 3/28/24 23:21, Nathaniel Shead wrote: > > > > - && !(modules_p () && DECL_DECLARED_INLINE_P (fn))) > > > > + && !(modules_p () > > > > + && (DECL_DECLARED_INLINE_P (fn) > > > > + || DECL_TEMPLATE_INSTANTIATION (fn)))) > > > > > > How about using vague_linkage_p? > > > > > > > Right, of course. How about this? > > Bootstrapped and regtested on x86_64-pc-linux-gnu, OK for trunk? > > > > -- >8 -- > > > > A template instantiation still needs to have its DECL_SAVED_TREE so that > > its definition is emitted into the CMI. This way it can be emitted in > > the object file of any importers that use it, in case it doesn't end up > > getting emitted in this TU. > > > > PR c++/104040 > > > > gcc/cp/ChangeLog: > > > > * semantics.cc (expand_or_defer_fn_1): Keep DECL_SAVED_TREE for > > all vague linkage functions. > > > > gcc/testsuite/ChangeLog: > > > > * g++.dg/modules/pr104040_a.C: New test. > > * g++.dg/modules/pr104040_b.C: New test. > > > > Signed-off-by: Nathaniel Shead <nathanielosh...@gmail.com> > > Reviewed-by: Jason Merrill <ja...@redhat.com> > > --- > > gcc/cp/semantics.cc | 5 +++-- > > gcc/testsuite/g++.dg/modules/pr104040_a.C | 14 ++++++++++++++ > > gcc/testsuite/g++.dg/modules/pr104040_b.C | 8 ++++++++ > > 3 files changed, 25 insertions(+), 2 deletions(-) > > create mode 100644 gcc/testsuite/g++.dg/modules/pr104040_a.C > > create mode 100644 gcc/testsuite/g++.dg/modules/pr104040_b.C > > > > diff --git a/gcc/cp/semantics.cc b/gcc/cp/semantics.cc > > index adb1ba48d29..03800a20b26 100644 > > --- a/gcc/cp/semantics.cc > > +++ b/gcc/cp/semantics.cc > > @@ -5033,9 +5033,10 @@ expand_or_defer_fn_1 (tree fn) > > /* We don't want to process FN again, so pretend we've written > > it out, even though we haven't. */ > > TREE_ASM_WRITTEN (fn) = 1; > > - /* If this is a constexpr function, keep DECL_SAVED_TREE. */ > > + /* If this is a constexpr function, or the body might need to be > > + exported from a module CMI, keep DECL_SAVED_TREE. */ > > if (!DECL_DECLARED_CONSTEXPR_P (fn) > > - && !(modules_p () && DECL_DECLARED_INLINE_P (fn))) > > + && !(modules_p () && vague_linkage_p (fn))) > > Also, how about module_maybe_has_cmi_p? OK with that change. > > Jason >
Using 'module_maybe_has_cmi_p' doesn't seem to work. This is for two reasons, one of them fixable and one of them not (easily): - It seems that header modules don't count for 'module_maybe_has_cmi_p'; I didn't notice this initially, and maybe they should for the no-linkage decls too? But even accounting for this, - For some reason only clearing it if the module might have a CMI causes crashes in importers for some testcases. I'm not 100% sure why yet, but I suspect it might be some duplicate-decls thing where the type inconsistently has DECL_SAVED_TREE applied, since this is also called on streamed-in declarations. Out of interest, what was the reason that it was cleared at all in the first place? I wasn't able to find anything with git blame; is it just for performance reasons in avoiding excess lowering later?
