compiler: don't perform semantic analysis if there are files without ZIR

src/Builtin.zig

@@ -299,7 +299,7 @@ pub fn populateFile(comp: *Compilation, mod: *Module, file: *File) !void {
 
     file.zir = try AstGen.generate(comp.gpa, file.tree.?);
     assert(!file.zir.?.hasCompileErrors()); // builtin.zig must not have astgen errors
-    file.status = .success_zir;
+    file.status = .success;
     // Note that whilst we set `zir` here, we populated `path_digest`
     // all the way back in `Package.Module.create`.
 }

src/Compilation.zig

@@ -3203,8 +3203,6 @@ pub fn getAllErrorsAlloc(comp: *Compilation) !ErrorBundle {
     }
 
     if (comp.zcu) |zcu| {
-        const ip = &zcu.intern_pool;
-
         for (zcu.failed_files.keys(), zcu.failed_files.values()) |file, error_msg| {
             if (error_msg) |msg| {
                 try addModuleErrorMsg(zcu, &bundle, msg.*);
@@ -3277,20 +3275,6 @@ pub fn getAllErrorsAlloc(comp: *Compilation) !ErrorBundle {
                 if (!refs.contains(anal_unit)) continue;
             }
 
-            report_ok: {
-                const file_index = switch (anal_unit.unwrap()) {
-                    .@"comptime" => |cu| ip.getComptimeUnit(cu).zir_index.resolveFile(ip),
-                    .nav_val, .nav_ty => |nav| ip.getNav(nav).analysis.?.zir_index.resolveFile(ip),
-                    .type => |ty| Type.fromInterned(ty).typeDeclInst(zcu).?.resolveFile(ip),
-                    .func => |ip_index| zcu.funcInfo(ip_index).zir_body_inst.resolveFile(ip),
-                    .memoized_state => break :report_ok, // always report std.builtin errors
-                };
-
-                // Skip errors for AnalUnits within files that had a parse failure.
-                // We'll try again once parsing succeeds.
-                if (!zcu.fileByIndex(file_index).okToReportErrors()) continue;
-            }
-
             std.log.scoped(.zcu).debug("analysis error '{s}' reported from unit '{}'", .{
                 error_msg.msg,
                 zcu.fmtAnalUnit(anal_unit),
@@ -3318,12 +3302,10 @@ pub fn getAllErrorsAlloc(comp: *Compilation) !ErrorBundle {
                 }
             }
         }
-        for (zcu.failed_codegen.keys(), zcu.failed_codegen.values()) |nav, error_msg| {
+        for (zcu.failed_codegen.values()) |error_msg| {
-            if (!zcu.navFileScope(nav).okToReportErrors()) continue;
             try addModuleErrorMsg(zcu, &bundle, error_msg.*);
         }
-        for (zcu.failed_types.keys(), zcu.failed_types.values()) |ty_index, error_msg| {
+        for (zcu.failed_types.values()) |error_msg| {
-            if (!zcu.typeFileScope(ty_index).okToReportErrors()) continue;
             try addModuleErrorMsg(zcu, &bundle, error_msg.*);
         }
         for (zcu.failed_exports.values()) |value| {
@@ -3827,12 +3809,35 @@ fn performAllTheWorkInner(
     if (comp.zcu) |zcu| {
         const pt: Zcu.PerThread = .activate(zcu, .main);
         defer pt.deactivate();
+
+        try reportMultiModuleErrors(pt);
+
+        const any_fatal_files = for (zcu.import_table.values()) |file_index| {
+            const file = zcu.fileByIndex(file_index);
+            if (file.getMode() == .zon) continue;
+            switch (file.status) {
+                .never_loaded => unreachable, // everything is loaded by the workers
+                .retryable_failure, .astgen_failure => break true,
+                .success => {},
+            }
+        } else false;
+
+        if (any_fatal_files) {
+            // We give up right now! No updating of ZIR refs, no nothing. The idea is that this prevents
+            // us from invalidating lots of incremental dependencies due to files with e.g. parse errors.
+            // However, this means our analysis data is invalid, so we want to omit all analysis errors.
+            // To do that, let's just clear the analysis roots!
+
+            assert(zcu.failed_files.count() > 0); // we will get an error
+            zcu.analysis_roots.clear(); // no analysis happened
+            return;
+        }
+
         if (comp.incremental) {
             const update_zir_refs_node = main_progress_node.start("Update ZIR References", 0);
             defer update_zir_refs_node.end();
             try pt.updateZirRefs();
         }
-        try reportMultiModuleErrors(pt);
         try zcu.flushRetryableFailures();
 
         zcu.sema_prog_node = main_progress_node.start("Semantic Analysis", 0);
@@ -4294,11 +4299,12 @@ fn workerAstGenFile(
     pt.astGenFile(file, path_digest) catch |err| switch (err) {
         error.AnalysisFail => return,
         else => {
-            file.status = .retryable_failure;
             pt.reportRetryableAstGenError(src, file_index, err) catch |oom| switch (oom) {
-                // Swallowing this error is OK because it's implied to be OOM when
+                error.OutOfMemory => {
-                // there is a missing `failed_files` error message.
+                    comp.mutex.lock();
-                error.OutOfMemory => {},
+                    defer comp.mutex.unlock();
+                    comp.setAllocFailure();
+                },
             };
             return;
         },

src/Package/Module.zig

@@ -488,7 +488,6 @@ pub fn create(arena: Allocator, options: CreateOptions) !*Package.Module {
             .zir = null,
             .zoir = null,
             .status = .never_loaded,
-            .prev_status = .never_loaded,
             .mod = new,
         };
         break :b new;

src/Zcu.zig

@@ -658,11 +658,27 @@ pub const Namespace = struct {
 };
 
 pub const File = struct {
-    status: Status,
-    prev_status: Status,
     /// Relative to the owning package's root source directory.
     /// Memory is stored in gpa, owned by File.
     sub_file_path: []const u8,
+
+    status: enum {
+        /// We have not yet attempted to load this file.
+        /// `stat` is not populated and may be `undefined`.
+        never_loaded,
+        /// A filesystem access failed. It should be retried on the next update.
+        /// There is a `failed_files` entry containing a non-`null` message.
+        /// `stat` is not populated and may be `undefined`.
+        retryable_failure,
+        /// Parsing/AstGen/ZonGen of this file has failed.
+        /// There is an error in `zir` or `zoir`.
+        /// There is a `failed_files` entry (with a `null` message).
+        /// `stat` is populated.
+        astgen_failure,
+        /// Parsing and AstGen/ZonGen of this file has succeeded.
+        /// `stat` is populated.
+        success,
+    },
     /// Whether this is populated depends on `status`.
     stat: Cache.File.Stat,
 
@@ -678,19 +694,17 @@ pub const File = struct {
     /// List of references to this file, used for multi-package errors.
     references: std.ArrayListUnmanaged(File.Reference) = .empty,
 
-    /// The most recent successful ZIR for this file, with no errors.
+    /// The ZIR for this file from the last update with no file failures. As such, this ZIR is never
-    /// This is only populated when a previously successful ZIR
+    /// failed (although it may have compile errors).
-    /// newly introduces compile errors during an update. When ZIR is
+    ///
-    /// successful, this field is unloaded.
+    /// Because updates with file failures do not perform ZIR mapping or semantic analysis, we keep
+    /// this around so we have the "old" ZIR to map when an update is ready to do so. Once such an
+    /// update occurs, this field is unloaded, since it is no longer necessary.
+    ///
+    /// In other words, if `TrackedInst`s are tied to ZIR other than what's in the `zir` field, this
+    /// field is populated with that old ZIR.
     prev_zir: ?*Zir = null,
 
-    pub const Status = enum {
-        never_loaded,
-        retryable_failure,
-        astgen_failure,
-        success_zir,
-    };
-
     /// A single reference to a file.
     pub const Reference = union(enum) {
         /// The file is imported directly (i.e. not as a package) with @import.
@@ -763,7 +777,7 @@ pub const File = struct {
             return error.FileTooBig;
 
         const source = try gpa.allocSentinel(u8, @as(usize, @intCast(stat.size)), 0);
-        defer gpa.free(source);
+        errdefer gpa.free(source);
 
         const amt = try f.readAll(source);
         if (amt != stat.size)
@@ -773,8 +787,9 @@ pub const File = struct {
         // used for error reporting. We need to keep the stat fields stale so that
         // astGenFile can know to regenerate ZIR.
 
-        errdefer comptime unreachable; // don't error after populating `source`
         file.source = source;
+        errdefer comptime unreachable; // don't error after populating `source`
+
         return .{
             .bytes = source,
             .stat = .{
@@ -849,13 +864,6 @@ pub const File = struct {
         std.debug.print("{s}:{d}:{d}\n", .{ file.sub_file_path, loc.line + 1, loc.column + 1 });
     }
 
-    pub fn okToReportErrors(file: File) bool {
-        return switch (file.status) {
-            .astgen_failure => false,
-            else => true,
-        };
-    }
-
     /// Add a reference to this file during AstGen.
     pub fn addReference(file: *File, zcu: *Zcu, ref: File.Reference) !void {
         // Don't add the same module root twice. Note that since we always add module roots at the
@@ -3295,19 +3303,6 @@ pub fn optimizeMode(zcu: *const Zcu) std.builtin.OptimizeMode {
     return zcu.root_mod.optimize_mode;
 }
 
-fn lockAndClearFileCompileError(zcu: *Zcu, file: *File) void {
-    switch (file.status) {
-        .success_zir, .retryable_failure => {},
-        .never_loaded, .astgen_failure => {
-            zcu.comp.mutex.lock();
-            defer zcu.comp.mutex.unlock();
-            if (zcu.failed_files.fetchSwapRemove(file)) |kv| {
-                if (kv.value) |msg| msg.destroy(zcu.gpa); // Delete previous error message.
-            }
-        },
-    }
-}
-
 pub fn handleUpdateExports(
     zcu: *Zcu,
     export_indices: []const Export.Index,
@@ -3662,9 +3657,7 @@ fn resolveReferencesInner(zcu: *Zcu) !std.AutoHashMapUnmanaged(AnalUnit, ?Resolv
                 // `test` declarations are analyzed depending on the test filter.
                 const inst_info = nav.analysis.?.zir_index.resolveFull(ip) orelse continue;
                 const file = zcu.fileByIndex(inst_info.file);
-                // If the file failed AstGen, the TrackedInst refers to the old ZIR.
+                const decl = file.zir.?.getDeclaration(inst_info.inst);
-                const zir = if (file.status == .success_zir) file.zir.? else file.prev_zir.?.*;
-                const decl = zir.getDeclaration(inst_info.inst);
 
                 if (!comp.config.is_test or file.mod != zcu.main_mod) continue;
 
@@ -3694,9 +3687,7 @@ fn resolveReferencesInner(zcu: *Zcu) !std.AutoHashMapUnmanaged(AnalUnit, ?Resolv
                 // These are named declarations. They are analyzed only if marked `export`.
                 const inst_info = ip.getNav(nav).analysis.?.zir_index.resolveFull(ip) orelse continue;
                 const file = zcu.fileByIndex(inst_info.file);
-                // If the file failed AstGen, the TrackedInst refers to the old ZIR.
+                const decl = file.zir.?.getDeclaration(inst_info.inst);
-                const zir = if (file.status == .success_zir) file.zir.? else file.prev_zir.?.*;
-                const decl = zir.getDeclaration(inst_info.inst);
                 if (decl.linkage == .@"export") {
                     const unit: AnalUnit = .wrap(.{ .nav_val = nav });
                     if (!result.contains(unit)) {
@@ -3712,9 +3703,7 @@ fn resolveReferencesInner(zcu: *Zcu) !std.AutoHashMapUnmanaged(AnalUnit, ?Resolv
                 // These are named declarations. They are analyzed only if marked `export`.
                 const inst_info = ip.getNav(nav).analysis.?.zir_index.resolveFull(ip) orelse continue;
                 const file = zcu.fileByIndex(inst_info.file);
-                // If the file failed AstGen, the TrackedInst refers to the old ZIR.
+                const decl = file.zir.?.getDeclaration(inst_info.inst);
-                const zir = if (file.status == .success_zir) file.zir.? else file.prev_zir.?.*;
-                const decl = zir.getDeclaration(inst_info.inst);
                 if (decl.linkage == .@"export") {
                     const unit: AnalUnit = .wrap(.{ .nav_val = nav });
                     if (!result.contains(unit)) {

src/Zcu/PerThread.zig

@@ -109,7 +109,7 @@ pub fn astGenFile(
 
             break :lock .shared;
         },
-        .astgen_failure, .success_zir => lock: {
+        .astgen_failure, .success => lock: {
             const unchanged_metadata =
                 stat.size == file.stat.size and
                 stat.mtime == file.stat.mtime and
@@ -214,8 +214,7 @@ pub fn astGenFile(
                 .inode = header.stat_inode,
                 .mtime = header.stat_mtime,
             };
-            file.prev_status = file.status;
+            file.status = .success;
-            file.status = .success_zir;
             log.debug("AstGen cached success: {s}", .{file.sub_file_path});
 
             if (file.zir.?.hasCompileErrors()) {
@@ -248,19 +247,11 @@ pub fn astGenFile(
 
     pt.lockAndClearFileCompileError(file);
 
-    // Previous ZIR is kept for two reasons:
+    // If `zir` is not null, and `prev_zir` is null, then `TrackedInst`s are associated with `zir`.
-    //
+    // We need to keep it around!
-    // 1. In case an update to the file causes a Parse or AstGen failure, we
+    // As an optimization, also check `loweringFailed`; if true, but `prev_zir == null`, then this
-    //    need to compare two successful ZIR files in order to proceed with an
+    // file has never passed AstGen, so we actually need not cache the old ZIR.
-    //    incremental update. This avoids needlessly tossing out semantic
+    if (file.zir != null and file.prev_zir == null and !file.zir.?.loweringFailed()) {
-    //    analysis work when an error is temporarily introduced.
-    //
-    // 2. In order to detect updates, we need to iterate over the intern pool
-    //    values while comparing old ZIR to new ZIR. This is better done in a
-    //    single-threaded context, so we need to keep both versions around
-    //    until that point in the pipeline. Previous ZIR data is freed after
-    //    that.
-    if (file.zir != null and !file.zir.?.loweringFailed()) {
         assert(file.prev_zir == null);
         const prev_zir_ptr = try gpa.create(Zir);
         file.prev_zir = prev_zir_ptr;
@@ -289,8 +280,7 @@ pub fn astGenFile(
 
     // Any potential AST errors are converted to ZIR errors here.
     file.zir = try AstGen.generate(gpa, file.tree.?);
-    file.prev_status = file.status;
+    file.status = .success;
-    file.status = .success_zir;
     log.debug("AstGen fresh success: {s}", .{file.sub_file_path});
 
     const safety_buffer = if (Zcu.data_has_safety_tag)
@@ -383,9 +373,7 @@ pub fn updateZirRefs(pt: Zcu.PerThread) Allocator.Error!void {
     defer cleanupUpdatedFiles(gpa, &updated_files);
     for (zcu.import_table.values()) |file_index| {
         const file = zcu.fileByIndex(file_index);
-        if (file.prev_status != file.status and file.prev_status != .never_loaded) {
+        assert(file.status == .success);
-            try zcu.markDependeeOutdated(.not_marked_po, .{ .file = file_index });
-        }
         const old_zir = file.prev_zir orelse continue;
         const new_zir = file.zir.?;
         const gop = try updated_files.getOrPut(gpa, file_index);
@@ -394,10 +382,8 @@ pub fn updateZirRefs(pt: Zcu.PerThread) Allocator.Error!void {
             .file = file,
             .inst_map = .{},
         };
-        if (!new_zir.loweringFailed()) {
         try Zcu.mapOldZirToNew(gpa, old_zir.*, new_zir, &gop.value_ptr.inst_map);
     }
-    }
 
     if (updated_files.count() == 0)
         return;
@@ -416,13 +402,9 @@ pub fn updateZirRefs(pt: Zcu.PerThread) Allocator.Error!void {
                 .index = @intCast(tracked_inst_unwrapped_index),
             }).wrap(ip);
             const new_inst = updated_file.inst_map.get(old_inst) orelse {
-                // Tracking failed for this instruction.
+                // Tracking failed for this instruction due to changes in the ZIR.
-                // This may be due to changes in the ZIR, or AstGen might have failed due to a very broken file.
+                // Invalidate associated `src_hash` deps.
-                // Either way, invalidate associated `src_hash` deps.
+                log.debug("tracking failed for %{d}", .{old_inst});
-                log.debug("tracking failed for %{d}{s}", .{
-                    old_inst,
-                    if (file.zir.?.loweringFailed()) " due to AstGen failure" else "",
-                });
                 tracked_inst.inst = .lost;
                 try zcu.markDependeeOutdated(.not_marked_po, .{ .src_hash = tracked_inst_index });
                 continue;
@@ -527,10 +509,7 @@ pub fn updateZirRefs(pt: Zcu.PerThread) Allocator.Error!void {
 
     for (updated_files.keys(), updated_files.values()) |file_index, updated_file| {
         const file = updated_file.file;
-        if (file.zir.?.loweringFailed()) {
+
-            // Keep `prev_zir` around: it's the last usable ZIR.
-            // Don't update the namespace, as we have no new data to update *to*.
-        } else {
         const prev_zir = file.prev_zir.?;
         file.prev_zir = null;
         prev_zir.deinit(gpa);
@@ -545,7 +524,6 @@ pub fn updateZirRefs(pt: Zcu.PerThread) Allocator.Error!void {
         try pt.updateFileNamespace(file_index);
     }
 }
-}
 
 /// Ensures that `zcu.fileRootType` on this `file_index` gives an up-to-date answer.
 /// Returns `error.AnalysisFail` if the file has an error.
@@ -745,6 +723,7 @@ pub fn ensureComptimeUnitUpToDate(pt: Zcu.PerThread, cu_id: InternPool.ComptimeU
                 kv.value.destroy(gpa);
             }
             _ = zcu.transitive_failed_analysis.swapRemove(anal_unit);
+            zcu.intern_pool.removeDependenciesForDepender(gpa, anal_unit);
         }
     } else {
         // We can trust the current information about this unit.
@@ -796,15 +775,8 @@ fn analyzeComptimeUnit(pt: Zcu.PerThread, cu_id: InternPool.ComptimeUnit.Id) Zcu
 
     const inst_resolved = comptime_unit.zir_index.resolveFull(ip) orelse return error.AnalysisFail;
     const file = zcu.fileByIndex(inst_resolved.file);
-    // TODO: stop the compiler ever reaching Sema if there are failed files. That way, this check is
-    // unnecessary, and we can move the below `removeDependenciesForDepender` call up with its friends
-    // in `ensureComptimeUnitUpToDate`.
-    if (file.status != .success_zir) return error.AnalysisFail;
     const zir = file.zir.?;
 
-    // We are about to re-analyze this unit; drop its depenndencies.
-    zcu.intern_pool.removeDependenciesForDepender(gpa, anal_unit);
-
     try zcu.analysis_in_progress.put(gpa, anal_unit, {});
     defer assert(zcu.analysis_in_progress.swapRemove(anal_unit));
 
@@ -923,6 +895,7 @@ pub fn ensureNavValUpToDate(pt: Zcu.PerThread, nav_id: InternPool.Nav.Index) Zcu
             kv.value.destroy(gpa);
         }
         _ = zcu.transitive_failed_analysis.swapRemove(anal_unit);
+        ip.removeDependenciesForDepender(gpa, anal_unit);
     } else {
         // We can trust the current information about this unit.
         if (prev_failed) return error.AnalysisFail;
@@ -993,15 +966,8 @@ fn analyzeNavVal(pt: Zcu.PerThread, nav_id: InternPool.Nav.Index) Zcu.CompileErr
 
     const inst_resolved = old_nav.analysis.?.zir_index.resolveFull(ip) orelse return error.AnalysisFail;
     const file = zcu.fileByIndex(inst_resolved.file);
-    // TODO: stop the compiler ever reaching Sema if there are failed files. That way, this check is
-    // unnecessary, and we can move the below `removeDependenciesForDepender` call up with its friends
-    // in `ensureComptimeUnitUpToDate`.
-    if (file.status != .success_zir) return error.AnalysisFail;
     const zir = file.zir.?;
 
-    // We are about to re-analyze this unit; drop its depenndencies.
-    zcu.intern_pool.removeDependenciesForDepender(gpa, anal_unit);
-
     try zcu.analysis_in_progress.put(gpa, anal_unit, {});
     errdefer _ = zcu.analysis_in_progress.swapRemove(anal_unit);
 
@@ -1301,6 +1267,7 @@ pub fn ensureNavTypeUpToDate(pt: Zcu.PerThread, nav_id: InternPool.Nav.Index) Zc
             kv.value.destroy(gpa);
         }
         _ = zcu.transitive_failed_analysis.swapRemove(anal_unit);
+        ip.removeDependenciesForDepender(gpa, anal_unit);
     } else {
         // We can trust the current information about this unit.
         if (prev_failed) return error.AnalysisFail;
@@ -1371,15 +1338,8 @@ fn analyzeNavType(pt: Zcu.PerThread, nav_id: InternPool.Nav.Index) Zcu.CompileEr
 
     const inst_resolved = old_nav.analysis.?.zir_index.resolveFull(ip) orelse return error.AnalysisFail;
     const file = zcu.fileByIndex(inst_resolved.file);
-    // TODO: stop the compiler ever reaching Sema if there are failed files. That way, this check is
-    // unnecessary, and we can move the below `removeDependenciesForDepender` call up with its friends
-    // in `ensureComptimeUnitUpToDate`.
-    if (file.status != .success_zir) return error.AnalysisFail;
     const zir = file.zir.?;
 
-    // We are about to re-analyze this unit; drop its depenndencies.
-    zcu.intern_pool.removeDependenciesForDepender(gpa, anal_unit);
-
     try zcu.analysis_in_progress.put(gpa, anal_unit, {});
     defer _ = zcu.analysis_in_progress.swapRemove(anal_unit);
 
@@ -1828,7 +1788,6 @@ fn updateFileNamespace(pt: Zcu.PerThread, file_index: Zcu.File.Index) Allocator.
     const zcu = pt.zcu;
 
     const file = zcu.fileByIndex(file_index);
-    assert(file.status == .success_zir);
     const file_root_type = zcu.fileRootType(file_index);
     if (file_root_type == .none) return;
 
@@ -1865,9 +1824,6 @@ fn semaFile(pt: Zcu.PerThread, file_index: Zcu.File.Index) Zcu.SemaError!void {
     assert(file.getMode() == .zig);
     assert(zcu.fileRootType(file_index) == .none);
 
-    if (file.status != .success_zir) {
-        return error.AnalysisFail;
-    }
     assert(file.zir != null);
 
     const new_namespace_index = try pt.createNamespace(.{
@@ -1910,7 +1866,7 @@ fn semaFile(pt: Zcu.PerThread, file_index: Zcu.File.Index) Zcu.SemaError!void {
     }
 }
 
-pub fn importPkg(pt: Zcu.PerThread, mod: *Module) !Zcu.ImportFileResult {
+pub fn importPkg(pt: Zcu.PerThread, mod: *Module) Allocator.Error!Zcu.ImportFileResult {
     const zcu = pt.zcu;
     const gpa = zcu.gpa;
 
@@ -1984,7 +1940,6 @@ pub fn importPkg(pt: Zcu.PerThread, mod: *Module) !Zcu.ImportFileResult {
         .zir = null,
         .zoir = null,
         .status = .never_loaded,
-        .prev_status = .never_loaded,
         .mod = mod,
     };
 
@@ -1997,13 +1952,19 @@ pub fn importPkg(pt: Zcu.PerThread, mod: *Module) !Zcu.ImportFileResult {
     };
 }
 
-/// Called from a worker thread during AstGen.
+/// Called from a worker thread during AstGen (with the Compilation mutex held).
 /// Also called from Sema during semantic analysis.
+/// Does not attempt to load the file from disk; just returns a corresponding `*Zcu.File`.
 pub fn importFile(
     pt: Zcu.PerThread,
     cur_file: *Zcu.File,
     import_string: []const u8,
-) !Zcu.ImportFileResult {
+) error{
+    OutOfMemory,
+    ModuleNotFound,
+    ImportOutsideModulePath,
+    CurrentWorkingDirectoryUnlinked,
+}!Zcu.ImportFileResult {
     const zcu = pt.zcu;
     const mod = cur_file.mod;
 
@@ -2061,7 +2022,10 @@ pub fn importFile(
     defer gpa.free(resolved_root_path);
 
     const sub_file_path = p: {
-        const relative = try std.fs.path.relative(gpa, resolved_root_path, resolved_path);
+        const relative = std.fs.path.relative(gpa, resolved_root_path, resolved_path) catch |err| switch (err) {
+            error.Unexpected => unreachable,
+            else => |e| return e,
+        };
         errdefer gpa.free(relative);
 
         if (!isUpDir(relative) and !std.fs.path.isAbsolute(relative)) {
@@ -2089,13 +2053,15 @@ pub fn importFile(
     gop.value_ptr.* = new_file_index;
     new_file.* = .{
         .sub_file_path = sub_file_path,
+
+        .status = .never_loaded,
         .stat = undefined,
+
         .source = null,
         .tree = null,
         .zir = null,
         .zoir = null,
-        .status = .never_loaded,
+
-        .prev_status = .never_loaded,
         .mod = mod,
     };
 
@@ -2835,7 +2801,7 @@ pub fn getErrorValueFromSlice(pt: Zcu.PerThread, name: []const u8) Allocator.Err
 /// `file.zir` must be unchanged from the last update, as it is used to determine if there is such an entry.
 fn lockAndClearFileCompileError(pt: Zcu.PerThread, file: *Zcu.File) void {
     const zir = file.zir orelse return;
-    if (zir.hasCompileErrors()) return;
+    if (!zir.hasCompileErrors()) return;
 
     pt.zcu.comp.mutex.lock();
     defer pt.zcu.comp.mutex.unlock();
@@ -3196,6 +3162,7 @@ pub fn linkerUpdateLineNumber(pt: Zcu.PerThread, ti: InternPool.TrackedInst.Inde
     }
 }
 
+/// Sets `File.status` of `file_index` to `retryable_failure`, and stores an error in `pt.zcu.failed_files`.
 pub fn reportRetryableAstGenError(
     pt: Zcu.PerThread,
     src: Zcu.AstGenSrc,
@@ -3231,13 +3198,18 @@ pub fn reportRetryableAstGenError(
     });
     errdefer err_msg.destroy(gpa);
 
-    {
     zcu.comp.mutex.lock();
     defer zcu.comp.mutex.unlock();
-        try zcu.failed_files.putNoClobber(gpa, file, err_msg);
+    const gop = try zcu.failed_files.getOrPut(gpa, file);
+    if (gop.found_existing) {
+        if (gop.value_ptr.*) |old_err_msg| {
+            old_err_msg.destroy(gpa);
         }
     }
+    gop.value_ptr.* = err_msg;
+}
 
+/// Sets `File.status` of `file_index` to `retryable_failure`, and stores an error in `pt.zcu.failed_files`.
 pub fn reportRetryableFileError(
     pt: Zcu.PerThread,
     file_index: Zcu.File.Index,
@@ -3771,7 +3743,6 @@ fn recreateStructType(
 
     const inst_info = key.zir_index.resolveFull(ip).?;
     const file = zcu.fileByIndex(inst_info.file);
-    assert(file.status == .success_zir); // otherwise inst tracking failed
     const zir = file.zir.?;
 
     assert(zir.instructions.items(.tag)[@intFromEnum(inst_info.inst)] == .extended);
@@ -3844,7 +3815,6 @@ fn recreateUnionType(
 
     const inst_info = key.zir_index.resolveFull(ip).?;
     const file = zcu.fileByIndex(inst_info.file);
-    assert(file.status == .success_zir); // otherwise inst tracking failed
     const zir = file.zir.?;
 
     assert(zir.instructions.items(.tag)[@intFromEnum(inst_info.inst)] == .extended);
@@ -3931,7 +3901,6 @@ fn recreateEnumType(
 
     const inst_info = key.zir_index.resolveFull(ip).?;
     const file = zcu.fileByIndex(inst_info.file);
-    assert(file.status == .success_zir); // otherwise inst tracking failed
     const zir = file.zir.?;
 
     assert(zir.instructions.items(.tag)[@intFromEnum(inst_info.inst)] == .extended);
@@ -4075,7 +4044,6 @@ pub fn ensureNamespaceUpToDate(pt: Zcu.PerThread, namespace_index: Zcu.Namespace
 
     const inst_info = key.zir_index.resolveFull(ip) orelse return error.AnalysisFail;
     const file = zcu.fileByIndex(inst_info.file);
-    if (file.status != .success_zir) return error.AnalysisFail;
     const zir = file.zir.?;
 
     assert(zir.instructions.items(.tag)[@intFromEnum(inst_info.inst)] == .extended);

src/main.zig

@@ -6134,7 +6134,6 @@ fn cmdAstCheck(
 
     var file: Zcu.File = .{
         .status = .never_loaded,
-        .prev_status = .never_loaded,
         .sub_file_path = undefined,
         .stat = undefined,
         .source = null,
@@ -6512,7 +6511,6 @@ fn cmdDumpZir(
 
     var file: Zcu.File = .{
         .status = .never_loaded,
-        .prev_status = .never_loaded,
         .sub_file_path = undefined,
         .stat = undefined,
         .source = null,
@@ -6578,7 +6576,6 @@ fn cmdChangelist(
 
     var file: Zcu.File = .{
         .status = .never_loaded,
-        .prev_status = .never_loaded,
         .sub_file_path = old_source_file,
         .stat = .{
             .size = stat.size,