diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 45174867e50..40e4c9ad330 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -185,6 +185,7 @@ jobs:
         env:
           # On stable the output messages will often not match pinned-nightly, so we set to 'overwrite'.
           TRYBUILD: ${{ matrix.rust_release == 'pinned-nightly' && 'wip' || 'overwrite' }}
+          HYDROFLOW_EXPECT_WARNINGS: ${{ matrix.rust_release == 'pinned-nightly' && 'noop' || 'ignore' }}
 
       - name: Run doctests
         run: cargo test --no-fail-fast --features python --features deploy --doc
diff --git a/hydroflow/src/declarative_macro.rs b/hydroflow/src/declarative_macro.rs
index 54d790c9c7b..12f8d3ece97 100644
--- a/hydroflow/src/declarative_macro.rs
+++ b/hydroflow/src/declarative_macro.rs
@@ -55,24 +55,32 @@ macro_rules! hydroflow_expect_warnings {
         $( , )?
     ) => {
         {
-            let __file = std::file!();
-            let __line = std::line!() as usize;
-            let __hf = hydroflow::hydroflow_syntax_noemit! $hf;
+            fn emit(msg: impl ::std::convert::AsRef<str>) {
+                if Ok("ignore") == ::std::env::var("HYDROFLOW_EXPECT_WARNINGS").as_deref() {
+                    eprintln!("{}", msg.as_ref());
+                } else {
+                    panic!("{}", msg.as_ref());
+                }
+            }
+
+            let __file = ::std::file!();
+            let __line = ::std::line!() as usize;
+            let __hf = $crate::hydroflow_syntax_noemit! $hf;
 
             let actuals = __hf.diagnostics().expect("Expected `diagnostics()` to be set.");
             let actuals_len = actuals.len();
-            let actuals = std::collections::BTreeSet::from_iter(actuals.iter().cloned().map(|mut actual| {
+            let actuals = ::std::collections::BTreeSet::from_iter(actuals.iter().cloned().map(|mut actual| {
                 actual.span.line = actual.span.line.saturating_sub(__line);
-                std::borrow::Cow::<'static, str>::Owned(actual.to_string().replace(__file, "$FILE"))
+                ::std::borrow::Cow::<'static, str>::Owned(actual.to_string().replace(__file, "$FILE"))
             }));
 
             let expecteds = [
                 $(
-                    std::borrow::Cow::Borrowed( $msg ),
+                    ::std::borrow::Cow::Borrowed( $msg ),
                 )*
             ];
             let expecteds_len = expecteds.len();
-            let expecteds = std::collections::BTreeSet::from(expecteds);
+            let expecteds = ::std::collections::BTreeSet::from(expecteds);
 
             let missing_errs = expecteds.difference(&actuals).map(|missing| {
                 format!("Expected diagnostic `{}` was not emitted.", missing)
@@ -80,13 +88,18 @@ macro_rules! hydroflow_expect_warnings {
             let extra_errs = actuals.difference(&expecteds).map(|extra| {
                 format!("Unexpected extra diagnostic `{}` was emitted", extra)
             });
-            let all_errs: Vec<_> = missing_errs.chain(extra_errs).collect();
+            let all_errs: ::std::vec::Vec<_> = missing_errs.chain(extra_errs).collect();
             if !all_errs.is_empty() {
-                panic!("{}", all_errs.join("\n"));
+                emit(all_errs.join("\n"));
             }
 
-            // TODO(mingwei): fix duplicates generated from multi-pass flow prop algorithm.
-            // assert_eq!(actuals_len, expecteds_len, "Wrong nubmer of diagnostics, were there duplicates?");
+            if actuals_len != expecteds_len {
+                emit(format!(
+                    "Number of expected warnings ({}) does not match number of actual warnings ({}), were there duplicates?",
+                    expecteds_len,
+                    actuals_len
+                ));
+            }
 
             __hf
         }
diff --git a/hydroflow/tests/surface_warnings.rs b/hydroflow/tests/surface_warnings.rs
index fa9826083cd..0b73113b271 100644
--- a/hydroflow/tests/surface_warnings.rs
+++ b/hydroflow/tests/surface_warnings.rs
@@ -1,7 +1,3 @@
-// TODO(mingwei): fix line numbers in tests
-// https://github.com/hydro-project/hydroflow/issues/729
-// https://github.com/rust-lang/rust/pull/111571
-
 use std::cell::RefCell;
 use std::rc::Rc;