Detection of missing implicit dependencies in dyndep files

src/build.cc

@@ -825,6 +825,17 @@ bool Builder::StartEdge(Edge* edge, string* err) {
   if (edge->is_phony())
     return true;
 
+  // Late validation: verify that dyndep‑only inputs are present.
+  for (const auto input : edge->inputs_) {
+    if (input->missing() && input->generated_by_dyndep_loader()) {
+      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) {
         }
       }
     }
+
+    // Refresh output file status to support later dyndep existence checks.
+    // https://github.com/ninja-build/ninja/issues/2573
+    for (auto o : edge->outputs_) {
+      o->MarkExists();
+    }
+
     if (node_cleaned) {
       record_mtime = edge->command_start_time_;
     }
@@ -998,7 +1016,7 @@ bool Builder::ExtractDeps(CommandRunner::Result* result,
       // all backslashes (as some of the slashes will certainly be backslashes
       // anyway). This could be fixed if necessary with some additional
       // complexity in IncludesNormalize::Relativize.
-      deps_nodes->push_back(state_->GetNode(*i, ~0u));
+      deps_nodes->push_back(state_->FindOrCreateDepfileNode(*i, ~0u));
     }
   } else if (deps_type == "gcc") {
     string depfile = result->edge->GetUnescapedDepfile();
@@ -1031,7 +1049,7 @@ bool Builder::ExtractDeps(CommandRunner::Result* result,
          i != deps.ins_.end(); ++i) {
       uint64_t slash_bits;
       CanonicalizePath(const_cast<char*>(i->str_), &i->len_, &slash_bits);
-      deps_nodes->push_back(state_->GetNode(*i, slash_bits));
+      deps_nodes->push_back(state_->FindOrCreateDepfileNode(*i, slash_bits));
     }
 
     if (!g_keep_depfile) {

src/build_test.cc

@@ -1044,6 +1044,7 @@ TEST_F(BuildTest, DepFileOK) {
   Edge* edge = state_.edges_.back();
 
   fs_.Create("foo.c", "");
+  state_.FindOrCreateDepfileNode("bar.h",0);  // create node 'bar.h'
   GetNode("bar.h")->MarkDirty();  // Mark bar.h as missing.
   fs_.Create("foo.o.d", "foo.o: blah.h bar.h\n");
   EXPECT_TRUE(builder_.AddTarget("foo.o", &err));
@@ -1231,7 +1232,8 @@ 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_.FindOrCreateDyndepNode("bar.h",0); // create node 'bar.h'
+  GetNode("bar.h")->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");
@@ -1969,7 +1971,7 @@ TEST_F(BuildWithLogTest, RestatInputChangesDueToRule) {
   // mtime
   EXPECT_TRUE(builder_.AddTarget("out1", &err));
   ASSERT_EQ("", err);
-  EXPECT_TRUE(!state_.GetNode("out1", 0)->dirty());
+  EXPECT_TRUE(!state_.GetNode("out1")->dirty());
   EXPECT_EQ(builder_.Build(&err), ExitSuccess);
   ASSERT_EQ("", err);
   EXPECT_EQ(size_t(1), command_runner_.commands_ran_.size());
@@ -3068,7 +3070,7 @@ TEST_F(BuildWithDepsLogTest, DepFileOKDepsLog) {
 
     Edge* edge = state.edges_.back();
 
-    state.GetNode("bar.h", 0)->MarkDirty();  // Mark bar.h as missing.
+    state.FindOrCreateDepfileNode("bar.h", 0)->MarkDirty(); // Mark bar.h as missing.
     EXPECT_TRUE(builder.AddTarget("fo o.o", &err));
     ASSERT_EQ("", err);
 
@@ -3214,7 +3216,7 @@ TEST_F(BuildWithDepsLogTest, DepFileDepsLogCanonicalize) {
     builder.command_runner_.reset(&command_runner_);
     SafeRelease protect(&builder);
 
-    state.GetNode("bar.h", 0)->MarkDirty();  // Mark bar.h as missing.
+    state.FindOrCreateDyndepNode("bar.h", 0)->MarkDirty();  // Mark bar.h as missing.
     EXPECT_TRUE(builder.AddTarget("a/b/c/d/e/fo o.o", &err));
     ASSERT_EQ("", err);
 
@@ -3365,6 +3367,61 @@ 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");
+
+  fs_.Create("tmp.imp", "");
+
+  string err;
+  EXPECT_TRUE(builder_.AddTarget("out", &err));
+  ASSERT_EQ("", err);
+  EXPECT_EQ(builder_.Build(&err), ExitFailure);
+  EXPECT_EQ("'missing.imp', needed by dyndep 'dd', missing and no known rule to make it", err);
+  EXPECT_TRUE(command_runner_.commands_ran_.empty());
+}
+
+TEST_F(BuildTest, DyndepMissingInputUsedInDepFile) {
+  // The missing input cannot be detected because the dyndep‑introduced node is
+  // also marked as coming from a depfile.
+  ASSERT_NO_FATAL_FAILURE(AssertParse(&state_,
+                                      R"ninja(
+rule touch
+  command = touch $out $out.imp
+build out2: touch out1 || dd
+  dyndep = dd
+build out1: touch
+  depfile = out2.d
+)ninja"));
+
+  fs_.Create("dd", R"ninja(
+ninja_dyndep_version = 1
+build out2 | out2.imp: dyndep | tmp.imp missing.imp
+)ninja");
+  fs_.Create("out2.d", "out1: missing.imp\n");
+  fs_.Create("tmp.imp", "");
+
+  string err;
+  EXPECT_TRUE(builder_.AddTarget("out2", &err));
+  ASSERT_EQ("", err);
+  EXPECT_EQ(builder_.Build(&err), ExitSuccess);
+  EXPECT_EQ("", err);
+  ASSERT_EQ(2u, command_runner_.commands_ran_.size());
+  EXPECT_EQ("touch out1 out1.imp", command_runner_.commands_ran_[0]);
+  EXPECT_EQ("touch out2 out2.imp", command_runner_.commands_ran_[1]);
+}
+
 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/deps_log.cc

@@ -252,7 +252,7 @@ LoadStatus DepsLog::Load(const string& path, State* state, string* err) {
       // have a correct slash_bits that GetNode will look up), or it is an
       // implicit dependency from a .d which does not affect the build command
       // (and so need not have its slashes maintained).
-      Node* node = state->GetNode(subpath, 0);
+      Node* node = state->FindOrCreateDepfileNode(subpath, 0);
 
       // Check that the expected index matches the actual index. This can only
       // happen if two ninja processes write to the same deps log concurrently.