Re: [PULL 12/40] rust: build integration test for the qemu_api crate

[Paolo Bonzini]

On Thu, Dec 19, 2024 at 12:22 PM Paolo Bonzini <pbonzini@redhat.com> wrote:
> On 12/19/24 10:53, Bernhard Beschow wrote:
> >
> >
> > Am 4. November 2024 17:26:51 UTC schrieb Paolo Bonzini <pbonzini@redhat.com>:
> >> Adjust the integration test to compile with a subset of QEMU object
> >> files, and make it actually create an object of the class it defines.
> >>
> >> Follow the Rust filesystem conventions, where tests go in tests/ if
> >> they use the library in the same way any other code would.
> >>
> >> Reviewed-by: Junjie Mao <junjie.mao@hotmail.com>
> >> Reviewed-by: Kevin Wolf <kwolf@redhat.com>
> >> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> >> ---
> >> meson.build                  | 10 ++++-
> >> rust/qemu-api/meson.build    | 26 ++++++++++--
> >> rust/qemu-api/src/lib.rs     |  3 --
> >> rust/qemu-api/src/tests.rs   | 49 ----------------------
> >> rust/qemu-api/tests/tests.rs | 78 ++++++++++++++++++++++++++++++++++++
> >> 5 files changed, 110 insertions(+), 56 deletions(-)
> >> delete mode 100644 rust/qemu-api/src/tests.rs
> >> create mode 100644 rust/qemu-api/tests/tests.rs
> >
> > When `--enable-modules` is passed to configure, this patch results in 
> numerous undefined symbols.
>
> Thanks for the report... This doesn't seem easy to fix without adding
> more hacks on top, but I'll try to do it right.

Which might very well be doing it in Meson.  One needs to teach Meson
to add --start-group/--end-group options for rustc just like Meson does
for the C compiler; or alternatively to support "objects: ..." for
Rust executables.

For example, with https://github.com/mesonbuild/meson/pull/14026, the fix
is simply this:

diff --git a/rust/qemu-api/meson.build b/rust/qemu-api/meson.build
index 9425ba7100c..0c08d2e51f5 100644
--- a/rust/qemu-api/meson.build
+++ b/rust/qemu-api/meson.build
@@ -59,7 +59,8 @@ test('rust-qemu-api-integration',
         rust_args: ['--test'],
         install: false,
         dependencies: [qemu_api, qemu_api_macros],
-        link_whole: [rust_qemu_api_objs, libqemuutil]),
+        link_with: libqemuutil,
+        link_whole: [rust_qemu_api_objs]),
     args: [
         '--test', '--test-threads', '1',
         '--format', 'pretty',

Until then, --enable-modules is broken together with Rust.

Paolo