Dyndep‑listed implicit dependencies were ignored when missing, mirroring depfile behavior.

Ninja now errors out when a dyndep input is missing and has no rule.

Author: moritzx22

src/build.cc

@@ -825,6 +825,17 @@ bool Builder::StartEdge(Edge* edge, string* err) {
   if (edge->is_phony())
     return true;
 
+  // late check if dyndep loaded inputs do exist
+  for (const auto input : edge->inputs_) {
+    if (input->missing() && input->get_dep_loader() == Node::Loader::Dyndep) {
+      string referenced;
+      referenced = ", needed by dyndep '" + edge->GetUnescapedDyndep() + "',";
+      *err = "'" + input->path() + "'" + referenced +
+             " missing and no known rule to make it";
+      return false;
+    }
+  }
+
   int64_t start_time_millis = GetTimeMillis() - start_time_millis_;
   running_edges_.insert(make_pair(edge, start_time_millis));
 
@@ -943,6 +954,13 @@ bool Builder::FinishCommand(CommandRunner::Result* result, string* err) {
         }
       }
     }
+
+    // update file status
+    // required to check if dyndep loaded input exists
+    for (auto o : edge->outputs_) {
+      o->MarkExists();
+    }
+
     if (node_cleaned) {
       record_mtime = edge->command_start_time_;
     }

src/build_test.cc

@@ -1231,7 +1231,7 @@ TEST_F(BuildTest, DepFileCanonicalize) {
 "build gen/stuff\\things/foo.o: cc x\\y/z\\foo.c\n"));
 
   fs_.Create("x/y/z/foo.c", "");
-  GetNode("bar.h")->MarkDirty();  // Mark bar.h as missing.
+  state_.GetNodeDeps("bar.h", 0)->MarkDirty();  // Mark bar.h as missing.
   // Note, different slashes from manifest.
   fs_.Create("gen/stuff\\things/foo.o.d",
              "gen\\stuff\\things\\foo.o: blah.h bar.h\n");
@@ -3214,7 +3214,7 @@ TEST_F(BuildWithDepsLogTest, DepFileDepsLogCanonicalize) {
     builder.command_runner_.reset(&command_runner_);
     SafeRelease protect(&builder);
 
-    state.GetNode("bar.h", 0)->MarkDirty();  // Mark bar.h as missing.
+    // bar.h as missing.
     EXPECT_TRUE(builder.AddTarget("a/b/c/d/e/fo o.o", &err));
     ASSERT_EQ("", err);
 
@@ -3365,6 +3365,28 @@ TEST_F(BuildTest, DyndepMissingAndNoRule) {
   EXPECT_EQ("loading 'dd': No such file or directory", err);
 }
 
+TEST_F(BuildTest, DyndepMissingInput) {
+  // Check that the build system detects when a dyndep-provided input is missing
+  ASSERT_NO_FATAL_FAILURE(AssertParse(&state_,
+                                      R"ninja(
+rule touch
+  command = touch $out $out.imp
+build out: touch || dd
+  dyndep = dd
+)ninja"));
+  fs_.Create("dd", R"ninja(
+ninja_dyndep_version = 1
+build out | out.imp: dyndep | tmp.imp missing.imp
+)ninja");
+
+  string err;
+  EXPECT_TRUE(builder_.AddTarget("out", &err));
+  ASSERT_EQ("", err);
+  EXPECT_EQ(builder_.Build(&err), ExitFailure);
+  EXPECT_EQ("'tmp.imp', needed by dyndep 'dd', missing and no known rule to make it", err);
+  EXPECT_TRUE(command_runner_.commands_ran_.empty());
+}
+
 TEST_F(BuildTest, DyndepReadyImplicitConnection) {
   // Verify that a dyndep file can be loaded immediately to discover
   // that one edge has an implicit output that is also an implicit

src/graph.h

@@ -41,7 +41,7 @@ struct State;
 /// it's dirty, mtime, etc.
 struct Node {
   enum class Loader : char { Depfile, Dyndep, Manifest };
-  
+
   Node(const std::string& path, uint64_t slash_bits, Loader loader)
       : path_(path), slash_bits_(slash_bits), generated_by_dep_loader_(loader) {}
 
@@ -77,6 +77,9 @@ struct Node {
     return exists_ == ExistenceStatusExists;
   }
 
+  void MarkExists() { exists_ = ExistenceStatusExists; }
+  bool missing() const { return exists_ == ExistenceStatusMissing; }
+
   bool status_known() const {
     return exists_ != ExistenceStatusUnknown;
   }
@@ -108,6 +111,11 @@ struct Node {
     return Loader::Manifest != generated_by_dep_loader_;
   }
 
+  // regular input or output from the Ninja manifest.
+  void set_generated_by_manifest() {
+    generated_by_dep_loader_ = Loader::Manifest;
+  }
+
   Loader get_dep_loader() const { return generated_by_dep_loader_; }
 
   int id() const { return id_; }

src/state.cc

@@ -110,7 +110,9 @@ Node* State::GetNode(StringPiece path, uint64_t slash_bits,
 }
 
 Node* State::GetNodeManifest(StringPiece path, uint64_t slash_bits) {
-  return GetNode(path, slash_bits, Node::Loader::Manifest);
+  auto node = GetNode(path, slash_bits, Node::Loader::Manifest);
+  node->set_generated_by_manifest();  // Manifest wins
+  return node;
 }
 
 Node* State::GetNodeDeps(StringPiece path, uint64_t slash_bits) {