diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_procmaps.h b/compiler-rt/lib/sanitizer_common/sanitizer_procmaps.h
index e03f1add7bf9..2cb64d1a8cd6 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_procmaps.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_procmaps.h
@@ -22,7 +22,7 @@ namespace __sanitizer {
 #if SANITIZER_WINDOWS
 class MemoryMappingLayout {
  public:
-  MemoryMappingLayout(bool cache_enabled) {
+  explicit MemoryMappingLayout(bool cache_enabled) {
     (void)cache_enabled;
   }
   bool GetObjectNameAndOffset(uptr addr, uptr *offset,