[Bug d/109108] d: Undefined reference to lambda in private enum

["cvs-commit at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109108

--- Comment #2 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-12 branch has been updated by Iain Buclaw
<ibuclaw@gcc.gnu.org>:

https://gcc.gnu.org/g:0dcfd68b2a8369b647650bb68ff612cad3b33ac9

commit r12-9252-g0dcfd68b2a8369b647650bb68ff612cad3b33ac9
Author: Iain Buclaw <ibuclaw@gdcproject.org>
Date:   Tue Mar 14 13:16:11 2023 +0100

    d: Fix undefined reference to lambda defined in private enum [PR109108]

    Previously lambdas were connected to the module they were defined in.
    Now they are emitted into every referencing compilation unit, and are
    given one-only linkage.

            PR d/109108

    gcc/d/ChangeLog:

            * decl.cc (function_defined_in_root_p): Remove.
            (get_symbol_decl): Set DECL_LAMBDA_FUNCTION_P on function literals.
            (start_function): Unconditionally unset DECL_EXTERNAL
            (set_linkage_for_decl): Give lambda functions one-only linkage.

    gcc/testsuite/ChangeLog:

            * gdc.dg/torture/imports/pr109108.d: New test.
            * gdc.dg/torture/pr109108.d: New test.

    (cherry picked from commit 423d34f61c43e400f0d5b837fe93c83963b2ecdd)