Commit 4a65cc4aca6fd03e80272a211e9b6c8c50716594 | zig

author	Matthew Lugg <mlugg@mlugg.co.uk> 2026-05-20 09:51:36+01:00
committer	Matthew Lugg <mlugg@mlugg.co.uk> 2026-05-20 16:27:04+02:00
log	4a65cc4aca6fd03e80272a211e9b6c8c50716594
tree	c2adba549fe8ae9cca555bf0c7cb1176802d5a58
parent	fec502ec674e458a53e846abb875e6591c3eacfb

Zcu: report outdated nav_ty when previous generation had a compile error

This logic existed when actually analyzing a `nav_ty` unit directly; it
was just missing in the code path which resolves a `nav_ty` unit due to
a `nav_val` being resolved.

Resolves: #35307

2 files changed, 35 insertions(+), 5 deletions(-)

src
- Zcu
  - PerThread.zig
test
- incremental
  - pointer_to_decl_with_astgen_error

src/Zcu/PerThread.zig+12-5

 @@ -1872,15 +1872,22 @@ fn analyzeNavVal(
     // that case and invalidate the dependee right now.
     if (zcu.clearOutdatedState(.wrap(.{ .nav_ty = nav_id }))) {
         assert(zir_decl.type_body == null); // otherwise we already resolved it with `Sema.ensureNavResolved`
-        zcu.resetUnit(.wrap(.{ .nav_ty = nav_id }));
+        const type_unit: AnalUnit = .wrap(.{ .nav_ty = nav_id });
-        try pt.addDependency(.wrap(.{ .nav_ty = nav_id }), .{ .nav_val = nav_id }); // inferred type depends on the value (that's us!)
+        const prev_type_failed = zcu.failed_analysis.contains(type_unit) or
+            zcu.transitive_failed_analysis.contains(type_unit);
+        zcu.resetUnit(type_unit);
+        try pt.addDependency(type_unit, .{ .nav_val = nav_id }); // inferred type depends on the value (that's us!)
         if (comp.debugIncremental()) {
-            const info = try zcu.incremental_debug_state.getUnitInfo(gpa, .wrap(.{ .nav_ty = nav_id }));
+            const info = try zcu.incremental_debug_state.getUnitInfo(gpa, type_unit);
             info.last_update_gen = zcu.generation;
             info.deps.clearRetainingCapacity();
         }
-        const type_changed: bool = if (old_nav.resolved) |r| r.type != nav_ty.toIntern() else true;
+        const type_outdated: bool = type_outdated: {
-        if (type_changed) {
+            if (prev_type_failed) break :type_outdated true;
+            const r = old_nav.resolved orelse break :type_outdated true;
+            break :type_outdated r.type != nav_ty.toIntern();
+        };
+        if (type_outdated) {
             try zcu.markDependeeOutdated(.marked_po, .{ .nav_ty = nav_id });
         } else {
             try zcu.markPoDependeeUpToDate(.{ .nav_ty = nav_id });

test/incremental/pointer_to_decl_with_astgen_error created+23

...	@@ -0,0 +1,23 @@
1	#update=initial version
2	#file=main.zig
3	const foo = {};
4	pub fn main() void {
5	_ = &foo;
6	}
7	#expect_stdout=""
8
9	#update=introduce use of undeclared identifier
10	#file=main.zig
11	const foo = something;
12	pub fn main() void {
13	_ = &foo;
14	}
15	#expect_error=main.zig:1:13: error: use of undeclared identifier 'something'
16
17	#update=revert use of undeclared identifier
18	#file=main.zig
19	const foo = {};
20	pub fn main() void {
21	_ = &foo;
22	}
23	#expect_stdout=""