MFV: zlib 1.2.5.

18 files changed, 117 insertions, 74 deletions

diff --git a/lib/libz/ChangeLog b/lib/libz/ChangeLog
index 898c197..f310bb0 100644
--- a/lib/libz/ChangeLog
+++ b/lib/libz/ChangeLog
@@ -1,6 +1,32 @@
 
                 ChangeLog file for zlib
 
+Changes in 1.2.5 (19 Apr 2010)
+- Disable visibility attribute in win32/Makefile.gcc [Bar-Lev]
+- Default to libdir as sharedlibdir in configure [Nieder]
+- Update copyright dates on modified source files
+- Update trees.c to be able to generate modified trees.h
+- Exit configure for MinGW, suggesting win32/Makefile.gcc
+
+Changes in 1.2.4.5 (18 Apr 2010)
+- Set sharedlibdir in configure [Torok]
+- Set LDFLAGS in Makefile.in [Bar-Lev]
+- Avoid mkdir objs race condition in Makefile.in [Bowler]
+- Add ZLIB_INTERNAL in front of internal inter-module functions and arrays
+- Define ZLIB_INTERNAL to hide internal functions and arrays for GNU C
+- Don't use hidden attribute when it is a warning generator (e.g. Solaris)
+
+Changes in 1.2.4.4 (18 Apr 2010)
+- Fix CROSS_PREFIX executable testing, CHOST extract, mingw* [Torok]
+- Undefine _LARGEFILE64_SOURCE in zconf.h if it is zero, but not if empty
+- Try to use bash or ksh regardless of functionality of /bin/sh
+- Fix configure incompatibility with NetBSD sh
+- Remove attempt to run under bash or ksh since have better NetBSD fix
+- Fix win32/Makefile.gcc for MinGW [Bar-Lev]
+- Add diagnostic messages when using CROSS_PREFIX in configure
+- Added --sharedlibdir option to configure [Weigelt]
+- Use hidden visibility attribute when available [Frysinger]
+
 Changes in 1.2.4.3 (10 Apr 2010)
 - Only use CROSS_PREFIX in configure for ar and ranlib if they exist
 - Use CROSS_PREFIX for nm [Bar-Lev]
@@ -151,7 +177,7 @@ Changes in 1.2.3.6 (17 Jan 2010)
 - Correct email address in configure for system options
 - Update make_vms.com and add make_vms.com to contrib/minizip [Zinser]
 - Update zlib.map [Brown]
-- Fix Makefile.in for Solaris 10 make of example64 and minizip64 [Tšršk]
+- Fix Makefile.in for Solaris 10 make of example64 and minizip64 [Torok]
 - Apply various fixes to CMakeLists.txt [Lowman]
 - Add checks on len in gzread() and gzwrite()
 - Add error message for no more room for gzungetc()
diff --git a/lib/libz/README b/lib/libz/README
index 68ff992..d4219bf 100644
--- a/lib/libz/README
+++ b/lib/libz/README
@@ -1,6 +1,6 @@
 ZLIB DATA COMPRESSION LIBRARY
 
-zlib 1.2.4.3 is a general purpose data compression library.  All the code is
+zlib 1.2.5 is a general purpose data compression library.  All the code is
 thread safe.  The data format used by the zlib library is described by RFCs
 (Request for Comments) 1950 to 1952 in the files
 http://www.ietf.org/rfc/rfc1950.txt (zlib format), rfc1951.txt (deflate format)
@@ -31,7 +31,7 @@ Mark Nelson <markn@ieee.org> wrote an article about zlib for the Jan.  1997
 issue of Dr.  Dobb's Journal; a copy of the article is available at
 http://marknelson.us/1997/01/01/zlib-engine/ .
 
-The changes made in version 1.2.4.3 are documented in the file ChangeLog.
+The changes made in version 1.2.5 are documented in the file ChangeLog.
 
 Unsupported third party contributions are provided in directory contrib/ .
 
diff --git a/lib/libz/crc32.c b/lib/libz/crc32.c
index 6b81fb4..91be372 100644
--- a/lib/libz/crc32.c
+++ b/lib/libz/crc32.c
@@ -1,5 +1,5 @@
 /* crc32.c -- compute the CRC-32 of a data stream
- * Copyright (C) 1995-2006 Mark Adler
+ * Copyright (C) 1995-2006, 2010 Mark Adler
  * For conditions of distribution and use, see copyright notice in zlib.h
  *
  * Thanks to Rodney Brown <rbrown64@csc.com.au> for his contribution of faster
diff --git a/lib/libz/deflate.c b/lib/libz/deflate.c
index efb26bf..5c4022f 100644
--- a/lib/libz/deflate.c
+++ b/lib/libz/deflate.c
@@ -52,7 +52,7 @@
 #include "deflate.h"
 
 const char deflate_copyright[] =
-   " deflate 1.2.4.3 Copyright 1995-2010 Jean-loup Gailly and Mark Adler ";
+   " deflate 1.2.5 Copyright 1995-2010 Jean-loup Gailly and Mark Adler ";
 /*
   If you use the zlib library in a product, an acknowledgment is welcome
   in the documentation of your product. If for some reason you cannot
diff --git a/lib/libz/deflate.h b/lib/libz/deflate.h
index f53deba..cbf0d1e 100644
--- a/lib/libz/deflate.h
+++ b/lib/libz/deflate.h
@@ -1,5 +1,5 @@
 /* deflate.h -- internal compression state
- * Copyright (C) 1995-2009 Jean-loup Gailly
+ * Copyright (C) 1995-2010 Jean-loup Gailly
  * For conditions of distribution and use, see copyright notice in zlib.h
  */
 
@@ -290,13 +290,13 @@ typedef struct internal_state {
    memory checker errors from longest match routines */
 
         /* in trees.c */
-void _tr_init         OF((deflate_state *s));
-int  _tr_tally        OF((deflate_state *s, unsigned dist, unsigned lc));
-void _tr_flush_block  OF((deflate_state *s, charf *buf, ulg stored_len,
-                          int last));
-void _tr_align        OF((deflate_state *s));
-void _tr_stored_block OF((deflate_state *s, charf *buf, ulg stored_len,
-                          int last));
+void ZLIB_INTERNAL _tr_init OF((deflate_state *s));
+int ZLIB_INTERNAL _tr_tally OF((deflate_state *s, unsigned dist, unsigned lc));
+void ZLIB_INTERNAL _tr_flush_block OF((deflate_state *s, charf *buf,
+                        ulg stored_len, int last));
+void ZLIB_INTERNAL _tr_align OF((deflate_state *s));
+void ZLIB_INTERNAL _tr_stored_block OF((deflate_state *s, charf *buf,
+                        ulg stored_len, int last));
 
 #define d_code(dist) \
    ((dist) < 256 ? _dist_code[dist] : _dist_code[256+((dist)>>7)])
@@ -309,11 +309,11 @@ void _tr_stored_block OF((deflate_state *s, charf *buf, ulg stored_len,
 /* Inline versions of _tr_tally for speed: */
 
 #if defined(GEN_TREES_H) || !defined(STDC)
-  extern uch _length_code[];
-  extern uch _dist_code[];
+  extern uch ZLIB_INTERNAL _length_code[];
+  extern uch ZLIB_INTERNAL _dist_code[];
 #else
-  extern const uch _length_code[];
-  extern const uch _dist_code[];
+  extern const uch ZLIB_INTERNAL _length_code[];
+  extern const uch ZLIB_INTERNAL _dist_code[];
 #endif
 
 # define _tr_tally_lit(s, c, flush) \
diff --git a/lib/libz/gzguts.h b/lib/libz/gzguts.h
index b0a4cbd..0f8fb79 100644
--- a/lib/libz/gzguts.h
+++ b/lib/libz/gzguts.h
@@ -12,7 +12,11 @@
 #  endif
 #endif
 
-#define ZLIB_INTERNAL
+#if ((__GNUC__-0) * 10 + __GNUC_MINOR__-0 >= 33) && !defined(NO_VIZ)
+#  define ZLIB_INTERNAL __attribute__((visibility ("hidden")))
+#else
+#  define ZLIB_INTERNAL
+#endif
 
 #include <stdio.h>
 #include "zlib.h"
@@ -112,9 +116,9 @@ typedef struct {
 typedef gz_state FAR *gz_statep;
 
 /* shared functions */
-ZEXTERN void ZEXPORT gz_error OF((gz_statep, int, const char *));
+void ZLIB_INTERNAL gz_error OF((gz_statep, int, const char *));
 #if defined UNDER_CE
-ZEXTERN char ZEXPORT *gz_strwinerror OF((DWORD error));
+char ZLIB_INTERNAL *gz_strwinerror OF((DWORD error));
 #endif
 
 /* GT_OFF(x), where x is an unsigned value, is true if x > maximum z_off64_t
@@ -123,6 +127,6 @@ ZEXTERN char ZEXPORT *gz_strwinerror OF((DWORD error));
 #ifdef INT_MAX
 #  define GT_OFF(x) (sizeof(int) == sizeof(z_off64_t) && (x) > INT_MAX)
 #else
-ZEXTERN unsigned ZEXPORT gz_intmax OF((void));
+unsigned ZLIB_INTERNAL gz_intmax OF((void));
 #  define GT_OFF(x) (sizeof(int) == sizeof(z_off64_t) && (x) > gz_intmax())
 #endif
diff --git a/lib/libz/gzlib.c b/lib/libz/gzlib.c
index f49fa8e..999455d 100644
--- a/lib/libz/gzlib.c
+++ b/lib/libz/gzlib.c
@@ -29,7 +29,7 @@ local gzFile gz_open OF((const char *, int, const char *));
 
    The gz_strwinerror function does not change the current setting of
    GetLastError. */
-char ZEXPORT *gz_strwinerror (error)
+char ZLIB_INTERNAL *gz_strwinerror (error)
      DWORD error;
 {
     static char buf[1024];
@@ -485,7 +485,7 @@ void ZEXPORT gzclearerr(file)
    memory).  Simply save the error message as a static string.  If there is an
    allocation failure constructing the error message, then convert the error to
    out of memory. */
-void ZEXPORT gz_error(state, err, msg)
+void ZLIB_INTERNAL gz_error(state, err, msg)
     gz_statep state;
     int err;
     const char *msg;
@@ -525,7 +525,7 @@ void ZEXPORT gz_error(state, err, msg)
    available) -- we need to do this to cover cases where 2's complement not
    used, since C standard permits 1's complement and sign-bit representations,
    otherwise we could just use ((unsigned)-1) >> 1 */
-unsigned ZEXPORT gz_intmax()
+unsigned ZLIB_INTERNAL gz_intmax()
 {
     unsigned p, q;
 
diff --git a/lib/libz/inffast.c b/lib/libz/inffast.c
index 0a0761f..2f1d60b 100644
--- a/lib/libz/inffast.c
+++ b/lib/libz/inffast.c
@@ -1,5 +1,5 @@
 /* inffast.c -- fast decoding
- * Copyright (C) 1995-2008 Mark Adler
+ * Copyright (C) 1995-2008, 2010 Mark Adler
  * For conditions of distribution and use, see copyright notice in zlib.h
  */
 
@@ -64,7 +64,7 @@
       requires strm->avail_out >= 258 for each loop to avoid checking for
       output space.
  */
-void inflate_fast(strm, start)
+void ZLIB_INTERNAL inflate_fast(strm, start)
 z_streamp strm;
 unsigned start;         /* inflate()'s starting value for strm->avail_out */
 {
diff --git a/lib/libz/inffast.h b/lib/libz/inffast.h
index 1e88d2d..e5c1aa4 100644
--- a/lib/libz/inffast.h
+++ b/lib/libz/inffast.h
@@ -1,5 +1,5 @@
 /* inffast.h -- header to use inffast.c
- * Copyright (C) 1995-2003 Mark Adler
+ * Copyright (C) 1995-2003, 2010 Mark Adler
  * For conditions of distribution and use, see copyright notice in zlib.h
  */
 
@@ -8,4 +8,4 @@
    subject to change. Applications should only use zlib.h.
  */
 
-void inflate_fast OF((z_streamp strm, unsigned start));
+void ZLIB_INTERNAL inflate_fast OF((z_streamp strm, unsigned start));
diff --git a/lib/libz/inftrees.c b/lib/libz/inftrees.c
index 430b174..11e9c52 100644
--- a/lib/libz/inftrees.c
+++ b/lib/libz/inftrees.c
@@ -9,7 +9,7 @@
 #define MAXBITS 15
 
 const char inflate_copyright[] =
-   " inflate 1.2.4.3 Copyright 1995-2010 Mark Adler ";
+   " inflate 1.2.5 Copyright 1995-2010 Mark Adler ";
 /*
   If you use the zlib library in a product, an acknowledgment is welcome
   in the documentation of your product. If for some reason you cannot
@@ -29,7 +29,7 @@ const char inflate_copyright[] =
    table index bits.  It will differ if the request is greater than the
    longest code or if it is less than the shortest code.
  */
-int inflate_table(type, lens, codes, table, bits, work)
+int ZLIB_INTERNAL inflate_table(type, lens, codes, table, bits, work)
 codetype type;
 unsigned short FAR *lens;
 unsigned codes;
@@ -62,7 +62,7 @@ unsigned short FAR *work;
         35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
     static const unsigned short lext[31] = { /* Length codes 257..285 extra */
         16, 16, 16, 16, 16, 16, 16, 16, 17, 17, 17, 17, 18, 18, 18, 18,
-        19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 16, 195, 66};
+        19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 16, 73, 195};
     static const unsigned short dbase[32] = { /* Distance codes 0..29 base */
         1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
         257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
diff --git a/lib/libz/inftrees.h b/lib/libz/inftrees.h
index 67461da..baa53a0 100644
--- a/lib/libz/inftrees.h
+++ b/lib/libz/inftrees.h
@@ -1,5 +1,5 @@
 /* inftrees.h -- header to use inftrees.c
- * Copyright (C) 1995-2005 Mark Adler
+ * Copyright (C) 1995-2005, 2010 Mark Adler
  * For conditions of distribution and use, see copyright notice in zlib.h
  */
 
@@ -57,6 +57,6 @@ typedef enum {
     DISTS
 } codetype;
 
-extern int inflate_table OF((codetype type, unsigned short FAR *lens,
+int ZLIB_INTERNAL inflate_table OF((codetype type, unsigned short FAR *lens,
                              unsigned codes, code FAR * FAR *table,
                              unsigned FAR *bits, unsigned short FAR *work));
diff --git a/lib/libz/trees.c b/lib/libz/trees.c
index 1a6e997..56e9bb1 100644
--- a/lib/libz/trees.c
+++ b/lib/libz/trees.c
@@ -1,5 +1,5 @@
 /* trees.c -- output deflated data using Huffman coding
- * Copyright (C) 1995-2009 Jean-loup Gailly
+ * Copyright (C) 1995-2010 Jean-loup Gailly
  * detect_data_type() function provided freely by Cosmin Truta, 2006
  * For conditions of distribution and use, see copyright notice in zlib.h
  */
@@ -351,13 +351,14 @@ void gen_trees_header()
                 static_dtree[i].Len, SEPARATOR(i, D_CODES-1, 5));
     }
 
-    fprintf(header, "const uch _dist_code[DIST_CODE_LEN] = {\n");
+    fprintf(header, "const uch ZLIB_INTERNAL _dist_code[DIST_CODE_LEN] = {\n");
     for (i = 0; i < DIST_CODE_LEN; i++) {
         fprintf(header, "%2u%s", _dist_code[i],
                 SEPARATOR(i, DIST_CODE_LEN-1, 20));
     }
 
-    fprintf(header, "const uch _length_code[MAX_MATCH-MIN_MATCH+1]= {\n");
+    fprintf(header,
+        "const uch ZLIB_INTERNAL _length_code[MAX_MATCH-MIN_MATCH+1]= {\n");
     for (i = 0; i < MAX_MATCH-MIN_MATCH+1; i++) {
         fprintf(header, "%2u%s", _length_code[i],
                 SEPARATOR(i, MAX_MATCH-MIN_MATCH, 20));
@@ -382,7 +383,7 @@ void gen_trees_header()
 /* ===========================================================================
  * Initialize the tree data structures for a new zlib stream.
  */
-void _tr_init(s)
+void ZLIB_INTERNAL _tr_init(s)
     deflate_state *s;
 {
     tr_static_init();
@@ -867,7 +868,7 @@ local void send_all_trees(s, lcodes, dcodes, blcodes)
 /* ===========================================================================
  * Send a stored block
  */
-void _tr_stored_block(s, buf, stored_len, last)
+void ZLIB_INTERNAL _tr_stored_block(s, buf, stored_len, last)
     deflate_state *s;
     charf *buf;       /* input block */
     ulg stored_len;   /* length of input block */
@@ -892,7 +893,7 @@ void _tr_stored_block(s, buf, stored_len, last)
  * To simplify the code, we assume the worst case of last real code encoded
  * on one bit only.
  */
-void _tr_align(s)
+void ZLIB_INTERNAL _tr_align(s)
     deflate_state *s;
 {
     send_bits(s, STATIC_TREES<<1, 3);
@@ -921,7 +922,7 @@ void _tr_align(s)
  * Determine the best encoding for the current block: dynamic trees, static
  * trees or store, and output the encoded block to the zip file.
  */
-void _tr_flush_block(s, buf, stored_len, last)
+void ZLIB_INTERNAL _tr_flush_block(s, buf, stored_len, last)
     deflate_state *s;
     charf *buf;       /* input block, or NULL if too old */
     ulg stored_len;   /* length of input block */
@@ -1022,7 +1023,7 @@ void _tr_flush_block(s, buf, stored_len, last)
  * Save the match info and tally the frequency counts. Return true if
  * the current block must be flushed.
  */
-int _tr_tally (s, dist, lc)
+int ZLIB_INTERNAL _tr_tally (s, dist, lc)
     deflate_state *s;
     unsigned dist;  /* distance of matched string */
     unsigned lc;    /* match length-MIN_MATCH or unmatched char (if dist==0) */
diff --git a/lib/libz/trees.h b/lib/libz/trees.h
index 72facf9..d35639d 100644
--- a/lib/libz/trees.h
+++ b/lib/libz/trees.h
@@ -70,7 +70,7 @@ local const ct_data static_dtree[D_CODES] = {
 {{19},{ 5}}, {{11},{ 5}}, {{27},{ 5}}, {{ 7},{ 5}}, {{23},{ 5}}
 };
 
-const uch _dist_code[DIST_CODE_LEN] = {
+const uch ZLIB_INTERNAL _dist_code[DIST_CODE_LEN] = {
  0,  1,  2,  3,  4,  4,  5,  5,  6,  6,  6,  6,  7,  7,  7,  7,  8,  8,  8,  8,
  8,  8,  8,  8,  9,  9,  9,  9,  9,  9,  9,  9, 10, 10, 10, 10, 10, 10, 10, 10,
 10, 10, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11,
@@ -99,7 +99,7 @@ const uch _dist_code[DIST_CODE_LEN] = {
 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29
 };
 
-const uch _length_code[MAX_MATCH-MIN_MATCH+1]= {
+const uch ZLIB_INTERNAL _length_code[MAX_MATCH-MIN_MATCH+1]= {
  0,  1,  2,  3,  4,  5,  6,  7,  8,  8,  9,  9, 10, 10, 11, 11, 12, 12, 12, 12,
 13, 13, 13, 13, 14, 14, 14, 14, 15, 15, 15, 15, 16, 16, 16, 16, 16, 16, 16, 16,
 17, 17, 17, 17, 17, 17, 17, 17, 18, 18, 18, 18, 18, 18, 18, 18, 19, 19, 19, 19,
diff --git a/lib/libz/zconf.h b/lib/libz/zconf.h
index 98cbe66..4efd6b2 100644
--- a/lib/libz/zconf.h
+++ b/lib/libz/zconf.h
@@ -315,10 +315,6 @@
 #  endif
 #endif
 
-#ifdef HAVE_VISIBILITY_PRAGMA
-#  define ZEXTERN __attribute__((visibility ("default"))) extern
-#endif
-
 #ifndef ZEXTERN
 #  define ZEXTERN extern
 #endif
@@ -368,6 +364,16 @@ typedef uLong FAR uLongf;
 #  include <sys/types.h>    /* for off_t */
 #endif
 
+/* a little trick to accommodate both "#define _LARGEFILE64_SOURCE" and
+ * "#define _LARGEFILE64_SOURCE 1" as requesting 64-bit operations, (even
+ * though the former does not conform to the LFS document), but considering
+ * both "#undef _LARGEFILE64_SOURCE" and "#define _LARGEFILE64_SOURCE 0" as
+ * equivalently requesting no 64-bit operations
+ */
+#if -_LARGEFILE64_SOURCE - -1 == 1
+#  undef _LARGEFILE64_SOURCE
+#endif
+
 #if defined(Z_HAVE_UNISTD_H) || defined(_LARGEFILE64_SOURCE)
 #  include <unistd.h>       /* for SEEK_* and off_t */
 #  ifdef VMS
diff --git a/lib/libz/zlib.3 b/lib/libz/zlib.3
index b534616..27adc4c 100644
--- a/lib/libz/zlib.3
+++ b/lib/libz/zlib.3
@@ -1,4 +1,4 @@
-.TH ZLIB 3 "10 Apr 2010"
+.TH ZLIB 3 "19 Apr 2010"
 .SH NAME
 zlib \- compression/decompression library
 .SH SYNOPSIS
@@ -125,7 +125,7 @@ before asking for help.
 Send questions and/or comments to zlib@gzip.org,
 or (for the Windows DLL version) to Gilles Vollant (info@winimage.com).
 .SH AUTHORS
-Version 1.2.4.3
+Version 1.2.5
 Copyright (C) 1995-2010 Jean-loup Gailly (jloup@gzip.org)
 and Mark Adler (madler@alumni.caltech.edu).
 .LP
diff --git a/lib/libz/zlib.h b/lib/libz/zlib.h
index 699630c..bfbba83 100644
--- a/lib/libz/zlib.h
+++ b/lib/libz/zlib.h
@@ -1,5 +1,5 @@
 /* zlib.h -- interface of the 'zlib' general purpose compression library
-  version 1.2.4.3, April 10th, 2010
+  version 1.2.5, April 19th, 2010
 
   Copyright (C) 1995-2010 Jean-loup Gailly and Mark Adler
 
@@ -37,12 +37,12 @@
 extern "C" {
 #endif
 
-#define ZLIB_VERSION "1.2.4.3"
-#define ZLIB_VERNUM 0x1243
+#define ZLIB_VERSION "1.2.5"
+#define ZLIB_VERNUM 0x1250
 #define ZLIB_VER_MAJOR 1
 #define ZLIB_VER_MINOR 2
-#define ZLIB_VER_REVISION 4
-#define ZLIB_VER_SUBREVISION 3
+#define ZLIB_VER_REVISION 5
+#define ZLIB_VER_SUBREVISION 0
 
 /*
     The 'zlib' compression library provides in-memory compression and
diff --git a/lib/libz/zutil.c b/lib/libz/zutil.c
index 6ba16f6..898ed34 100644
--- a/lib/libz/zutil.c
+++ b/lib/libz/zutil.c
@@ -1,5 +1,5 @@
 /* zutil.c -- target dependent utility functions for the compression library
- * Copyright (C) 1995-2005 Jean-loup Gailly.
+ * Copyright (C) 1995-2005, 2010 Jean-loup Gailly.
  * For conditions of distribution and use, see copyright notice in zlib.h
  */
 
@@ -117,9 +117,9 @@ uLong ZEXPORT zlibCompileFlags()
 #  ifndef verbose
 #    define verbose 0
 #  endif
-int z_verbose = verbose;
+int ZLIB_INTERNAL z_verbose = verbose;
 
-void z_error (m)
+void ZLIB_INTERNAL z_error (m)
     char *m;
 {
     fprintf(stderr, "%s\n", m);
@@ -146,7 +146,7 @@ const char * ZEXPORT zError(err)
 
 #ifndef HAVE_MEMCPY
 
-void zmemcpy(dest, source, len)
+void ZLIB_INTERNAL zmemcpy(dest, source, len)
     Bytef* dest;
     const Bytef* source;
     uInt  len;
@@ -157,7 +157,7 @@ void zmemcpy(dest, source, len)
     } while (--len != 0);
 }
 
-int zmemcmp(s1, s2, len)
+int ZLIB_INTERNAL zmemcmp(s1, s2, len)
     const Bytef* s1;
     const Bytef* s2;
     uInt  len;
@@ -170,7 +170,7 @@ int zmemcmp(s1, s2, len)
     return 0;
 }
 
-void zmemzero(dest, len)
+void ZLIB_INTERNAL zmemzero(dest, len)
     Bytef* dest;
     uInt  len;
 {
@@ -213,7 +213,7 @@ local ptr_table table[MAX_PTR];
  * a protected system like OS/2. Use Microsoft C instead.
  */
 
-voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
+voidpf ZLIB_INTERNAL zcalloc (voidpf opaque, unsigned items, unsigned size)
 {
     voidpf buf = opaque; /* just to make some compilers happy */
     ulg bsize = (ulg)items*size;
@@ -237,7 +237,7 @@ voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
     return buf;
 }
 
-void  zcfree (voidpf opaque, voidpf ptr)
+void ZLIB_INTERNAL zcfree (voidpf opaque, voidpf ptr)
 {
     int n;
     if (*(ush*)&ptr != 0) { /* object < 64K */
@@ -272,13 +272,13 @@ void  zcfree (voidpf opaque, voidpf ptr)
 #  define _hfree   hfree
 #endif
 
-voidpf zcalloc (voidpf opaque, uInt items, uInt size)
+voidpf ZLIB_INTERNAL zcalloc (voidpf opaque, uInt items, uInt size)
 {
     if (opaque) opaque = 0; /* to make compiler happy */
     return _halloc((long)items, size);
 }
 
-void  zcfree (voidpf opaque, voidpf ptr)
+void ZLIB_INTERNAL zcfree (voidpf opaque, voidpf ptr)
 {
     if (opaque) opaque = 0; /* to make compiler happy */
     _hfree(ptr);
@@ -297,7 +297,7 @@ extern voidp  calloc OF((uInt items, uInt size));
 extern void   free   OF((voidpf ptr));
 #endif
 
-voidpf zcalloc (opaque, items, size)
+voidpf ZLIB_INTERNAL zcalloc (opaque, items, size)
     voidpf opaque;
     unsigned items;
     unsigned size;
@@ -307,7 +307,7 @@ voidpf zcalloc (opaque, items, size)
                               (voidpf)calloc(items, size);
 }
 
-void  zcfree (opaque, ptr)
+void ZLIB_INTERNAL zcfree (opaque, ptr)
     voidpf opaque;
     voidpf ptr;
 {
diff --git a/lib/libz/zutil.h b/lib/libz/zutil.h
index a250088..258fa88 100644
--- a/lib/libz/zutil.h
+++ b/lib/libz/zutil.h
@@ -13,7 +13,12 @@
 #ifndef ZUTIL_H
 #define ZUTIL_H
 
-#define ZLIB_INTERNAL
+#if ((__GNUC__-0) * 10 + __GNUC_MINOR__-0 >= 33) && !defined(NO_VIZ)
+#  define ZLIB_INTERNAL __attribute__((visibility ("hidden")))
+#else
+#  define ZLIB_INTERNAL
+#endif
+
 #include "zlib.h"
 
 #ifdef STDC
@@ -231,16 +236,16 @@ extern const char * const z_errmsg[10]; /* indexed by 2-zlib_error */
 #    define zmemzero(dest, len) memset(dest, 0, len)
 #  endif
 #else
-   extern void zmemcpy  OF((Bytef* dest, const Bytef* source, uInt len));
-   extern int  zmemcmp  OF((const Bytef* s1, const Bytef* s2, uInt len));
-   extern void zmemzero OF((Bytef* dest, uInt len));
+   void ZLIB_INTERNAL zmemcpy OF((Bytef* dest, const Bytef* source, uInt len));
+   int ZLIB_INTERNAL zmemcmp OF((const Bytef* s1, const Bytef* s2, uInt len));
+   void ZLIB_INTERNAL zmemzero OF((Bytef* dest, uInt len));
 #endif
 
 /* Diagnostic functions */
 #ifdef DEBUG
 #  include <stdio.h>
-   extern int z_verbose;
-   extern void z_error    OF((char *m));
+   extern int ZLIB_INTERNAL z_verbose;
+   extern void ZLIB_INTERNAL z_error OF((char *m));
 #  define Assert(cond,msg) {if(!(cond)) z_error(msg);}
 #  define Trace(x) {if (z_verbose>=0) fprintf x ;}
 #  define Tracev(x) {if (z_verbose>0) fprintf x ;}
@@ -257,8 +262,9 @@ extern const char * const z_errmsg[10]; /* indexed by 2-zlib_error */
 #endif
 
 
-voidpf zcalloc OF((voidpf opaque, unsigned items, unsigned size));
-void   zcfree  OF((voidpf opaque, voidpf ptr));
+voidpf ZLIB_INTERNAL zcalloc OF((voidpf opaque, unsigned items,
+                        unsigned size));
+void ZLIB_INTERNAL zcfree  OF((voidpf opaque, voidpf ptr));
 
 #define ZALLOC(strm, items, size) \
            (*((strm)->zalloc))((strm)->opaque, (items), (size))