fix(tvix/eval): type check function argument with set pattern r/6243

C++ Nix forces and typechecks the passed argument even if it is not
necessary in order to compute the return value of the function. I
discovered this when I thought our formals miscompilation might be that
we are too strict, but doesn't look like it in this case.

Change-Id: Ifb3c92592293052c489d1e3ae8c7c54e4b6b4dc6
Reviewed-on: https://cl.tvl.fyi/c/depot/+/8701
Tested-by: BuildkiteCI
Autosubmit: sterni <sternenseemann@systemli.org>
Reviewed-by: tazjin <tazjin@tvl.su>

1 files changed, 1 insertions, 0 deletions

diff --git a/tvix/eval/src/compiler/mod.rs b/tvix/eval/src/compiler/mod.rs
index 75d9d94475a2..450799d683d1 100644
--- a/tvix/eval/src/compiler/mod.rs
+++ b/tvix/eval/src/compiler/mod.rs
@@ -910,6 +910,7 @@ impl Compiler<'_> {
         // the stack.
         self.scope_mut().mark_initialised(set_idx);
         self.emit_force(pattern);
+        self.push_op(OpCode::OpAssertAttrs, pattern);
 
         let ellipsis = pattern.ellipsis_token().is_some();
         if !ellipsis {