On Fri, 29 Mar 2024, Nathaniel Shead wrote:
> Bootstrapped and regtested on x86_64-pc-linux-gnu, OK for trunk?
LGTM
>
> -- >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): Also keep DECL_SAVED_TREE
> for template instantiations.
>
> 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>
> ---
> gcc/cp/semantics.cc | 7 +++++--
> gcc/testsuite/g++.dg/modules/pr104040_a.C | 14 ++++++++++++++
> gcc/testsuite/g++.dg/modules/pr104040_b.C | 8 ++++++++
> 3 files changed, 27 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..84e9901509a 100644
> --- a/gcc/cp/semantics.cc
> +++ b/gcc/cp/semantics.cc
> @@ -5033,9 +5033,12 @@ 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 ()
> + && (DECL_DECLARED_INLINE_P (fn)
> + || DECL_TEMPLATE_INSTANTIATION (fn))))
> DECL_SAVED_TREE (fn) = NULL_TREE;
> return false;
> }
> diff --git a/gcc/testsuite/g++.dg/modules/pr104040_a.C
> b/gcc/testsuite/g++.dg/modules/pr104040_a.C
> new file mode 100644
> index 00000000000..ea36ce0a798
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/pr104040_a.C
> @@ -0,0 +1,14 @@
> +// PR c++/104040
> +// { dg-additional-options "-fmodules-ts" }
> +// { dg-module-cmi test }
> +
> +export module test;
> +
> +export template <typename T>
> +struct test {
> + ~test() {}
> +};
> +
> +test<bool> use() {
> + return {};
> +}
> diff --git a/gcc/testsuite/g++.dg/modules/pr104040_b.C
> b/gcc/testsuite/g++.dg/modules/pr104040_b.C
> new file mode 100644
> index 00000000000..efe014673fb
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/pr104040_b.C
> @@ -0,0 +1,8 @@
> +// PR c++/104040
> +// { dg-additional-options "-fmodules-ts" }
> +
> +import test;
> +
> +int main() {
> + test<bool> t{};
> +}
> --
> 2.43.2
>
>
