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
@@ -55,6 +55,14 @@
 
   Optimize(CI);
 
+  // The original invocation probably didn't have strict context hash enabled.
+  // We will use the context hash of this invocation to distinguish between
+  // multiple incompatible versions of the same module and will use it when
+  // reporting dependencies to the clients. Let's make sure we're using
+  // **strict** context hash in order to prevent accidental sharing of
+  // incompatible modules (e.g. with differences in search paths).
+  CI.getHeaderSearchOpts().ModulesStrictContextHash = true;
+
   return CI;
 }
 
diff --git a/clang/test/ClangScanDeps/Inputs/modules-context-hash/a/dep.h b/clang/test/ClangScanDeps/Inputs/modules-context-hash/a/dep.h
new file mode 100644
diff --git a/clang/test/ClangScanDeps/Inputs/modules-context-hash/b/dep.h b/clang/test/ClangScanDeps/Inputs/modules-context-hash/b/dep.h
new file mode 100644
diff --git a/clang/test/ClangScanDeps/Inputs/modules-context-hash/cdb.json.template b/clang/test/ClangScanDeps/Inputs/modules-context-hash/cdb.json.template
new file mode 100644
--- /dev/null
+++ b/clang/test/ClangScanDeps/Inputs/modules-context-hash/cdb.json.template
@@ -0,0 +1,12 @@
+[
+  {
+    "directory": "DIR",
+    "command": "clang -c DIR/tu.c -fmodules -fmodules-cache-path=DIR/cache -IDIR/a -o DIR/tu_a.o",
+    "file": "DIR/tu.c"
+  },
+  {
+    "directory": "DIR",
+    "command": "clang -c DIR/tu.c -fmodules -fmodules-cache-path=DIR/cache -IDIR/b -o DIR/tu_b.o",
+    "file": "DIR/tu.c"
+  }
+]
diff --git a/clang/test/ClangScanDeps/Inputs/modules-context-hash/mod.h b/clang/test/ClangScanDeps/Inputs/modules-context-hash/mod.h
new file mode 100644
--- /dev/null
+++ b/clang/test/ClangScanDeps/Inputs/modules-context-hash/mod.h
@@ -0,0 +1 @@
+#include "dep.h"
diff --git a/clang/test/ClangScanDeps/Inputs/modules-context-hash/module.modulemap b/clang/test/ClangScanDeps/Inputs/modules-context-hash/module.modulemap
new file mode 100644
--- /dev/null
+++ b/clang/test/ClangScanDeps/Inputs/modules-context-hash/module.modulemap
@@ -0,0 +1 @@
+module mod { header "mod.h" }
diff --git a/clang/test/ClangScanDeps/Inputs/modules-context-hash/tu.c b/clang/test/ClangScanDeps/Inputs/modules-context-hash/tu.c
new file mode 100644
--- /dev/null
+++ b/clang/test/ClangScanDeps/Inputs/modules-context-hash/tu.c
@@ -0,0 +1 @@
+#include "mod.h"
diff --git a/clang/test/ClangScanDeps/modules-context-hash.c b/clang/test/ClangScanDeps/modules-context-hash.c
new file mode 100644
--- /dev/null
+++ b/clang/test/ClangScanDeps/modules-context-hash.c
@@ -0,0 +1,89 @@
+// RUN: rm -rf %t && mkdir %t
+// RUN: cp -r %S/Inputs/modules-context-hash/* %t
+
+// Check that the scanner reports the same module as distinct dependencies when
+// a single translation unit gets compiled with multiple command-lines that
+// produce different **strict** context hashes.
+
+// RUN: sed "s|DIR|%/t|g" %S/Inputs/modules-context-hash/cdb.json.template > %t/cdb.json
+// RUN: echo -%t > %t/result.json
+// RUN: clang-scan-deps -compilation-database %t/cdb.json -format experimental-full -j 1 >> %t/result.json
+// RUN: cat %t/result.json | sed 's:\\\\\?:/:g' | FileCheck %s -check-prefix=CHECK
+
+// CHECK:      -[[PREFIX:.*]]
+// CHECK-NEXT: {
+// CHECK-NEXT:   "modules": [
+// CHECK-NEXT:     {
+// CHECK-NEXT:       "clang-module-deps": [],
+// CHECK-NEXT:       "clang-modulemap-file": "[[PREFIX]]/module.modulemap",
+// CHECK-NEXT:       "command-line": [
+// CHECK-NEXT:         "-cc1"
+// CHECK:              "-emit-module"
+// CHECK:              "-I"
+// CHECK:              "[[PREFIX]]/a"
+// CHECK:              "-fmodule-name=mod"
+// CHECK:            ],
+// CHECK-NEXT:       "context-hash": "[[HASH_MOD_A:.*]]",
+// CHECK-NEXT:       "file-deps": [
+// CHECK-NEXT:         "[[PREFIX]]/a/dep.h",
+// CHECK-NEXT:         "[[PREFIX]]/mod.h",
+// CHECK-NEXT:         "[[PREFIX]]/module.modulemap"
+// CHECK-NEXT:       ],
+// CHECK-NEXT:       "name": "mod"
+// CHECK-NEXT:     },
+// CHECK-NEXT:     {
+// CHECK-NEXT:       "clang-module-deps": [],
+// CHECK-NEXT:       "clang-modulemap-file": "[[PREFIX]]/module.modulemap",
+// CHECK-NEXT:       "command-line": [
+// CHECK-NEXT:         "-cc1"
+// CHECK:              "-emit-module"
+// CHECK:              "-I"
+// CHECK:              "[[PREFIX]]/b"
+// CHECK:              "-fmodule-name=mod"
+// CHECK:            ],
+// CHECK-NEXT:       "context-hash": "[[HASH_MOD_B:.*]]",
+// CHECK-NEXT:       "file-deps": [
+// CHECK-NEXT:         "[[PREFIX]]/b/dep.h",
+// CHECK-NEXT:         "[[PREFIX]]/mod.h",
+// CHECK-NEXT:         "[[PREFIX]]/module.modulemap"
+// CHECK-NEXT:       ],
+// CHECK-NEXT:       "name": "mod"
+// CHECK-NEXT:     }
+// CHECK-NEXT:   ],
+// CHECK-NEXT:   "translation-units": [
+// CHECK-NEXT:     {
+// CHECK-NEXT:       "clang-context-hash": "{{.*}}",
+// CHECK-NEXT:       "clang-module-deps": [
+// CHECK-NEXT:         {
+// CHECK-NEXT:           "context-hash": "[[HASH_MOD_A]]",
+// CHECK-NEXT:           "module-name": "mod"
+// CHECK-NEXT:         }
+// CHECK-NEXT:       ],
+// CHECK-NEXT:       "command-line": [
+// CHECK-NEXT:         "-fno-implicit-modules",
+// CHECK-NEXT:         "-fno-implicit-module-maps"
+// CHECK-NEXT:       ],
+// CHECK-NEXT:       "file-deps": [
+// CHECK-NEXT:         "[[PREFIX]]/tu.c"
+// CHECK-NEXT:       ],
+// CHECK-NEXT:       "input-file": "[[PREFIX]]/tu.c"
+// CHECK-NEXT:     },
+// CHECK-NEXT:     {
+// CHECK-NEXT:       "clang-context-hash": "{{.*}}",
+// CHECK-NEXT:       "clang-module-deps": [
+// CHECK-NEXT:         {
+// CHECK-NEXT:           "context-hash": "[[HASH_MOD_B]]",
+// CHECK-NEXT:           "module-name": "mod"
+// CHECK-NEXT:         }
+// CHECK-NEXT:       ],
+// CHECK-NEXT:       "command-line": [
+// CHECK-NEXT:         "-fno-implicit-modules",
+// CHECK-NEXT:         "-fno-implicit-module-maps"
+// CHECK-NEXT:       ],
+// CHECK-NEXT:       "file-deps": [
+// CHECK-NEXT:         "[[PREFIX]]/tu.c"
+// CHECK-NEXT:       ],
+// CHECK-NEXT:       "input-file": "[[PREFIX]]/tu.c"
+// CHECK-NEXT:     }
+// CHECK-NEXT:   ]
+// CHECK-NEXT: }