diff --git a/src/ccstruct/ccstruct.cpp b/src/ccstruct/ccstruct.cpp
index 151df33e1e..4d188c4137 100644
--- a/src/ccstruct/ccstruct.cpp
+++ b/src/ccstruct/ccstruct.cpp
@@ -28,4 +28,9 @@ const double CCStruct::kAscenderFraction = 0.25;
 const double CCStruct::kXHeightCapRatio = CCStruct::kXHeightFraction /
     (CCStruct::kXHeightFraction + CCStruct::kAscenderFraction);
 
+// Destructor.
+// It is defined here, so the compiler can create a single vtable
+// instead of weak vtables in every compilation unit.
+CCStruct::~CCStruct() = default;
+
 }
diff --git a/src/ccstruct/ccstruct.h b/src/ccstruct/ccstruct.h
index dfdf77bfe2..8979ea33ff 100644
--- a/src/ccstruct/ccstruct.h
+++ b/src/ccstruct/ccstruct.h
@@ -25,7 +25,7 @@ namespace tesseract {
 class CCStruct : public CUtil {
  public:
   CCStruct() = default;
-  ~CCStruct() = default;
+  virtual ~CCStruct();
 
   // Globally accessible constants.
   // APPROXIMATIONS of the fractions of the character cell taken by