updated test-gzstd
diff --git a/programs/fileio.c b/programs/fileio.c
index 743a5ec..f860145 100644
--- a/programs/fileio.c
+++ b/programs/fileio.c
@@ -35,6 +35,9 @@
 #include "zstd.h"
 #ifdef ZSTD_GZDECOMPRESS
 #include "zlib.h"
+#if !defined(z_const)
+    #define z_const
+#endif
 #endif
 
 
@@ -632,7 +635,7 @@
         if (ZSTD_isError(readSizeHint)) EXM_THROW(36, "Decoding error : %s", ZSTD_getErrorName(readSizeHint));
 
         /* Write block */
-        storedSkips = FIO_fwriteSparse(ress->dstFile, ress->dstBuffer, outBuff.pos, storedSkips);
+        storedSkips = FIO_fwriteSparse(ress->dstFile, ress->dstBuffer, outBuff.pos, storedSkips);       
         frameSize += outBuff.pos;
         DISPLAYUPDATE(2, "\rDecoded : %u MB...     ", (U32)((alreadyDecoded+frameSize)>>20) );
 
diff --git a/tests/Makefile b/tests/Makefile
index ca899d2..ad36759 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -194,9 +194,14 @@
 test-zstd-nolegacy: zstd-nolegacy zstd-playTests
 
 test-gzstd: gzstd
+	$(PRGDIR)/zstd README.md test-zstd-speed.py
 	gzip README.md test-zstd-speed.py
+	cat README.md.zst test-zstd-speed.py.gz >zstd_gz.zst
+	cat README.md.gz test-zstd-speed.py.zst >gz_zstd.gz
 	$(PRGDIR)/zstd -d README.md.gz -o README2.md
 	$(PRGDIR)/zstd -d README.md.gz test-zstd-speed.py.gz
+	$(PRGDIR)/zstd -d zstd_gz.zst gz_zstd.gz
+	diff -q zstd_gz gz_zstd
 
 test-fullbench: fullbench datagen
 	$(QEMU_SYS) ./fullbench -i1