diff --git a/libcxx/test/libcxx/module_std.gen.py b/libcxx/test/libcxx/module_std.gen.py
--- a/libcxx/test/libcxx/module_std.gen.py
+++ b/libcxx/test/libcxx/module_std.gen.py
@@ -225,3 +225,10 @@
 
 # Compare the sum of the parts with the main module.
 print(f"// RUN{BLOCKLIT}: diff -u %t.all_partitions %t.module")
+
+# Basic smoke test. Import a module and try to compile when using all
+# exported names. This validates the clang-tidy script does not accidentally
+# add named declarations to the list that are not available.
+print(f"// RUN{BLOCKLIT}: echo 'import std;' > %t.compile.pass.cpp")
+print(f"// RUN{BLOCKLIT}: cat %t.all_partitions >> %t.compile.pass.cpp")
+print(f"// RUN{BLOCKLIT}: %{{cxx}} %{{flags}} %{{compile_flags}} -fsyntax-only %t.compile.pass.cpp")
diff --git a/libcxx/test/tools/clang_tidy_checks/header_exportable_declarations.cpp b/libcxx/test/tools/clang_tidy_checks/header_exportable_declarations.cpp
--- a/libcxx/test/tools/clang_tidy_checks/header_exportable_declarations.cpp
+++ b/libcxx/test/tools/clang_tidy_checks/header_exportable_declarations.cpp
@@ -228,6 +228,11 @@
       if (clang::Module* M = decl->getOwningModule(); M && M->Kind != clang::Module::ModulePartitionInterface)
         return;
 
+    // For module partitions only take exported declarations.
+    if (file_type_ == FileType::ModulePartition)
+      if (decl->getModuleOwnershipKind() != clang::Decl::ModuleOwnershipKind::VisibleWhenImported)
+        return;
+
     if (decls_.contains(name)) {
       // For modules avoid exporting the same named declaration twice. For
       // header files this is common and valid.