--- gpdf-2.8.2.orig/xpdf/TextOutputDev.h
+++ gpdf-2.8.2/xpdf/TextOutputDev.h
@@ -166,6 +166,8 @@
 // TextLine
 //------------------------------------------------------------------------
 
+class TextBlock;
+
 class TextLine {
 public:
 
@@ -223,6 +225,8 @@
 // TextBlock
 //------------------------------------------------------------------------
 
+class TextPage;
+
 class TextBlock {
 public:
 
@@ -342,6 +346,8 @@
 // TextPage
 //------------------------------------------------------------------------
 
+class TextLineFrag;
+
 class TextPage {
 public: