diff --git a/clang/include/clang/Tooling/DependencyScanning/ModuleDepCollector.h b/clang/include/clang/Tooling/DependencyScanning/ModuleDepCollector.h
--- a/clang/include/clang/Tooling/DependencyScanning/ModuleDepCollector.h
+++ b/clang/include/clang/Tooling/DependencyScanning/ModuleDepCollector.h
@@ -19,6 +19,7 @@
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/StringSet.h"
 #include "llvm/Support/raw_ostream.h"
+#include <optional>
 #include <string>
 #include <unordered_map>
 
@@ -161,7 +162,8 @@
   /// Traverses the previously collected direct modular dependencies to discover
   /// transitive modular dependencies and fills the parent \c ModuleDepCollector
   /// with both.
-  ModuleID handleTopLevelModule(const Module *M);
+  /// Returns the ID or nothing if the dependency is spurious and is ignored.
+  std::optional<ModuleID> handleTopLevelModule(const Module *M);
   void addAllSubmoduleDeps(const Module *M, ModuleDeps &MD,
                            llvm::DenseSet<const Module *> &AddedModules);
   void addModuleDep(const Module *M, ModuleDeps &MD,
diff --git a/clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp b/clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp
--- a/clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp
+++ b/clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp
@@ -377,15 +377,8 @@
     if (!MDC.isPrebuiltModule(M))
       DirectModularDeps.insert(M);
 
-  for (const Module *M : DirectModularDeps) {
-    // A top-level module might not be actually imported as a module when
-    // -fmodule-name is used to compile a translation unit that imports this
-    // module. In that case it can be skipped. The appropriate header
-    // dependencies will still be reported as expected.
-    if (!M->getASTFile())
-      continue;
+  for (const Module *M : DirectModularDeps)
     handleTopLevelModule(M);
-  }
 
   MDC.Consumer.handleDependencyOutputOpts(*MDC.Opts);
 
@@ -399,9 +392,17 @@
     MDC.Consumer.handlePrebuiltModuleDependency(I.second);
 }
 
-ModuleID ModuleDepCollectorPP::handleTopLevelModule(const Module *M) {
+std::optional<ModuleID>
+ModuleDepCollectorPP::handleTopLevelModule(const Module *M) {
   assert(M == M->getTopLevelModule() && "Expected top level module!");
 
+  // A top-level module might not be actually imported as a module when
+  // -fmodule-name is used to compile a translation unit that imports this
+  // module. In that case it can be skipped. The appropriate header
+  // dependencies will still be reported as expected.
+  if (!M->getASTFile())
+    return {};
+
   // If this module has been handled already, just return its ID.
   auto ModI = MDC.ModularDeps.insert({M, nullptr});
   if (!ModI.second)
@@ -522,9 +523,9 @@
   for (const Module *Import : M->Imports) {
     if (Import->getTopLevelModule() != M->getTopLevelModule() &&
         !MDC.isPrebuiltModule(Import)) {
-      ModuleID ImportID = handleTopLevelModule(Import->getTopLevelModule());
-      if (AddedModules.insert(Import->getTopLevelModule()).second)
-        MD.ClangModuleDeps.push_back(ImportID);
+      if (auto ImportID = handleTopLevelModule(Import->getTopLevelModule()))
+        if (AddedModules.insert(Import->getTopLevelModule()).second)
+          MD.ClangModuleDeps.push_back(*ImportID);
     }
   }
 }
@@ -546,9 +547,9 @@
            "Not quite import not top-level module");
     if (Affecting != M->getTopLevelModule() &&
         !MDC.isPrebuiltModule(Affecting)) {
-      ModuleID ImportID = handleTopLevelModule(Affecting);
-      if (AddedModules.insert(Affecting).second)
-        MD.ClangModuleDeps.push_back(ImportID);
+      if (auto ImportID = handleTopLevelModule(Affecting))
+        if (AddedModules.insert(Affecting).second)
+          MD.ClangModuleDeps.push_back(*ImportID);
     }
   }
 }
diff --git a/clang/test/ClangScanDeps/modules-implementation-private.m b/clang/test/ClangScanDeps/modules-implementation-private.m
new file mode 100644
--- /dev/null
+++ b/clang/test/ClangScanDeps/modules-implementation-private.m
@@ -0,0 +1,70 @@
+// This test checks that we don't crash or report spurious dependencies on
+// FW_Private when compiling the implementation of framework module FW.
+
+// RUN: rm -rf %t
+// RUN: split-file %s %t
+
+//--- cdb.json.template
+[{
+  "directory": "DIR",
+  "file": "DIR/tu.m",
+  "command": "clang -fmodules -fmodules-cache-path=DIR/cache -fmodule-name=FW -F DIR/frameworks -c DIR/tu.m -o DIR/tu.o"
+}]
+
+//--- frameworks/FW.framework/Modules/module.modulemap
+framework module FW { umbrella header "FW.h" }
+//--- frameworks/FW.framework/Modules/module.private.modulemap
+framework module FW_Private { umbrella header "FW_Private.h" }
+//--- frameworks/FW.framework/Headers/FW.h
+//--- frameworks/FW.framework/PrivateHeaders/FW_Private.h
+//--- frameworks/FW.framework/PrivateHeaders/Missed.h
+#import <FW/FW.h> // When included from tu.m, this ends up adding (spurious) dependency on FW for FW_Private.
+
+//--- tu.m
+@import FW_Private; // This is a direct dependency.
+#import <FW/Missed.h>
+
+// RUN: sed "s|DIR|%/t|g" %t/cdb.json.template > %t/cdb.json
+// RUN: clang-scan-deps -compilation-database %t/cdb.json -format experimental-full > %t/result.json
+// RUN: cat %t/result.json | sed 's:\\\\\?:/:g' | FileCheck %s -DPREFIX=%/t
+
+// CHECK:      {
+// CHECK-NEXT:   "modules": [
+// CHECK-NEXT:     {
+// CHECK-NEXT:       "clang-module-deps": [],
+// CHECK-NEXT:       "clang-modulemap-file": "[[PREFIX]]/frameworks/FW.framework/Modules/module.private.modulemap",
+// CHECK-NEXT:       "command-line": [
+// CHECK:            ],
+// CHECK-NEXT:       "context-hash": "{{.*}}",
+// CHECK-NEXT:       "file-deps": [
+// CHECK-NEXT:         "[[PREFIX]]/frameworks/FW.framework/Modules/module.private.modulemap",
+// CHECK-NEXT:         "[[PREFIX]]/frameworks/FW.framework/PrivateHeaders/FW_Private.h"
+// CHECK-NEXT:       ],
+// CHECK-NEXT:       "name": "FW_Private"
+// CHECK-NEXT:     }
+// CHECK-NEXT:   ],
+// CHECK-NEXT:   "translation-units": [
+// CHECK-NEXT:     {
+// CHECK-NEXT:       "commands": [
+// CHECK-NEXT:         {
+// CHECK-NEXT:           "clang-context-hash": "{{.*}}",
+// CHECK-NEXT:           "clang-module-deps": [
+// CHECK-NEXT:             {
+// CHECK-NEXT:               "context-hash": "{{.*}}",
+// CHECK-NEXT:               "module-name": "FW_Private"
+// CHECK-NEXT:             }
+// CHECK-NEXT:           ],
+// CHECK-NEXT:           "command-line": [
+// CHECK:                ],
+// CHECK-NEXT:           "executable": "clang",
+// CHECK-NEXT:           "file-deps": [
+// CHECK-NEXT:             "[[PREFIX]]/tu.m",
+// CHECK-NEXT:             "[[PREFIX]]/frameworks/FW.framework/PrivateHeaders/Missed.h",
+// CHECK-NEXT:             "[[PREFIX]]/frameworks/FW.framework/Headers/FW.h"
+// CHECK-NEXT:           ],
+// CHECK-NEXT:           "input-file": "[[PREFIX]]/tu.m"
+// CHECK-NEXT:         }
+// CHECK:            ]
+// CHECK:          }
+// CHECK:        ]
+// CHECK:      }