1 files changed, 5 insertions, 0 deletions
diff --git a/clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp b/clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp
index e19f19b2..f46324e 100644
--- a/clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp
+++ b/clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp
@@ -179,6 +179,11 @@ makeCommonInvocationForModuleBuild(CompilerInvocation CI) {
   CI.resetNonModularOptions();
   CI.clearImplicitModuleBuildOptions();
 
+  // The scanner takes care to avoid passing non-affecting module maps to the
+  // explicit compiles. No need to do extra work just to find out there are no
+  // module map files to prune.
+  CI.getHeaderSearchOpts().ModulesPruneNonAffectingModuleMaps = false;
+
   // Remove options incompatible with explicit module build or are likely to
   // differ between identical modules discovered from different translation
   // units.