diff --git a/src/bin/pg_dump/compress_io.h b/src/bin/pg_dump/compress_io.h
index 8edf2b1ea6d..bbf450a3890 100644
--- a/src/bin/pg_dump/compress_io.h
+++ b/src/bin/pg_dump/compress_io.h
@@ -22,8 +22,6 @@
 #define ZLIB_OUT_SIZE	4096
 #define ZLIB_IN_SIZE	4096
 
-struct _CompressorState;
-
 typedef enum
 {
 	COMPR_ALG_NONE,