rust: track inline module scopes for module file resolution

[mathstuf]

The set of inline modules is required to find the expected location of a
module file. Track this information with an RAII object
(InlineModuleStackScope) and pass it down to any out-of-line modules
so that, when requested, the set of inline modules can be added to the
search path.

Signed-off-by: Ben Boeckel [email protected]

---

Note that this does not include a test case because I have no idea how to mark up this for all the warnings that come out (#676):

diff --git a/gcc/testsuite/rust/compile/missing_middle/sub/mod.rs b/gcc/testsuite/rust/compile/missing_middle/sub/mod.rs
new file mode 100644
index 00000000000..f099d61e04a
--- /dev/null
+++ b/gcc/testsuite/rust/compile/missing_middle/sub/mod.rs
@@ -0,0 +1,3 @@
+pub fn f() -> u32 {
+    1
+}
diff --git a/gcc/testsuite/rust/compile/mod_missing_middle.rs b/gcc/testsuite/rust/compile/mod_missing_middle.rs
new file mode 100644
index 00000000000..d9cdf0a54f1
--- /dev/null
+++ b/gcc/testsuite/rust/compile/mod_missing_middle.rs
@@ -0,0 +1,11 @@
+pub mod missing_middle {
+    pub mod sub;
+}

Observed warnings:

/home/boeckb/code/depot/group-compilers/gcc/src-gccrs/gcc/testsuite/rust/compile/missing_middle/sub/mod.rs:1:5: warning: unused name 'f'
/home/boeckb/code/depot/group-compilers/gcc/src-gccrs/gcc/testsuite/rust/compile/mod_missing_middle.rs:2:9: warning: unused name 'sub'
/home/boeckb/code/depot/group-compilers/gcc/src-gccrs/gcc/testsuite/rust/compile/missing_middle/sub/mod.rs:1:5: warning: unused name 'sub::f'
/home/boeckb/code/depot/group-compilers/gcc/src-gccrs/gcc/testsuite/rust/compile/mod_missing_middle.rs:2:9: warning: unused name 'missing_middle::sub'
/home/boeckb/code/depot/group-compilers/gcc/src-gccrs/gcc/testsuite/rust/compile/mod_missing_middle.rs:1:5: warning: unused name 'missing_middle'
/home/boeckb/code/depot/group-compilers/gcc/src-gccrs/gcc/testsuite/rust/compile/missing_middle/sub/mod.rs:1:5: warning: unused name 'missing_middle::sub::f'

Fixes: #645

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[CohenArthur]

Thanks :D I think the PR needs some tests before it gets merged, I can take a look at the warning thingies

[CohenArthur]

Ah, @mathstuf: You can add the following to the test cases for now to remove (unused) warnings:

// { dg-additional-options "-w" }
mod modules;

fn main() {
    let twelve = modules::return_12();
}

the issues you are seeing are because of name resolution. I faced them too when implementing the little bits for module inclusion

[mathstuf]

OK, so something isn't quite right with #[path] yet, but I'll look at that later.

[mathstuf]

Gah. Mutable local variables bite again. #[path] issues resolved.

[philberty]

I don't think this PR relates to the #635 I think its this one you mean #645

[philberty]

Nice work, I think it looks good but I would like to see any new classes have private fields if possible its not always the case so let me know.

[mathstuf]

OK, so I've updated to support #[path = "…"] mod inline {} as well. The test suite needed an update.

I'll also note that it seems that inline modules don't support inner attributes.

[philberty]

LGTM

[CohenArthur]

Apart from the copied function I think this is all good :D Thanks a lot!

[CohenArthur]

Thanks! LGTM!

[CohenArthur]

bors r+

[bors]

Build succeeded:

• build-and-check
• clang-format