zlib: fix compiler warnings

metze
(This used to be commit ce44a608f66bf27070fd43d576551fde6f545d7c)

12 files changed, 80 insertions, 74 deletions

diff --git a/source4/lib/zlib/adler32.c b/source4/lib/zlib/adler32.c
index 007ba26277..b5333d7b8e 100644
--- a/source4/lib/zlib/adler32.c
+++ b/source4/lib/zlib/adler32.c
@@ -5,8 +5,7 @@
 
 /* @(#) $Id$ */
 
-#define ZLIB_INTERNAL
-#include "zlib.h"
+#include "zutil.h"
 
 #define BASE 65521UL    /* largest prime smaller than 65536 */
 #define NMAX 5552
diff --git a/source4/lib/zlib/compress.c b/source4/lib/zlib/compress.c
index df04f0148e..40a53cd476 100644
--- a/source4/lib/zlib/compress.c
+++ b/source4/lib/zlib/compress.c
@@ -5,8 +5,7 @@
 
 /* @(#) $Id$ */
 
-#define ZLIB_INTERNAL
-#include "zlib.h"
+#include "zutil.h"
 
 /* ===========================================================================
      Compresses the source buffer into the destination buffer. The level
@@ -29,7 +28,7 @@ int ZEXPORT compress2 (dest, destLen, source, sourceLen, level)
     z_stream stream;
     int err;
 
-    stream.next_in = (Bytef*)source;
+    stream.next_in = source;
     stream.avail_in = (uInt)sourceLen;
 #ifdef MAXSEG_64K
     /* Check for source > 64K on 16-bit machine: */
diff --git a/source4/lib/zlib/crc32.c b/source4/lib/zlib/crc32.c
index f658a9ef55..4d6e699e60 100644
--- a/source4/lib/zlib/crc32.c
+++ b/source4/lib/zlib/crc32.c
@@ -11,6 +11,8 @@
 
 /* @(#) $Id$ */
 
+#include "zutil.h"      /* for STDC and FAR definitions */
+
 /*
   Note on the use of DYNAMIC_CRC_TABLE: there is no mutex or semaphore
   protection on the static variables used to control the first-use generation
@@ -26,8 +28,6 @@
 #  endif /* !DYNAMIC_CRC_TABLE */
 #endif /* MAKECRCH */
 
-#include "zutil.h"      /* for STDC and FAR definitions */
-
 #define local static
 
 /* Find a four-byte integer type for crc32_little() and crc32_big(). */
diff --git a/source4/lib/zlib/deflate.c b/source4/lib/zlib/deflate.c
index 29ce1f64a5..2720aab911 100644
--- a/source4/lib/zlib/deflate.c
+++ b/source4/lib/zlib/deflate.c
@@ -154,9 +154,6 @@ local const config configuration_table[10] = {
  * meaning.
  */
 
-#define EQUAL 0
-/* result of memcmp for equal strings */
-
 #ifndef NO_DUMMY_DECL
 struct static_tree_desc_s {int dummy;}; /* for buggy compilers */
 #endif
@@ -297,7 +294,7 @@ int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
     if (s->window == Z_NULL || s->prev == Z_NULL || s->head == Z_NULL ||
         s->pending_buf == Z_NULL) {
         s->status = FINISH_STATE;
-        strm->msg = (char*)ERR_MSG(Z_MEM_ERROR);
+        strm->msg = ERR_MSG(Z_MEM_ERROR);
         deflateEnd (strm);
         return Z_MEM_ERROR;
     }
@@ -1226,6 +1223,9 @@ local uInt longest_match_fast(s, cur_match)
 }
 
 #ifdef DEBUG
+#define EQUAL 0
+/* result of memcmp for equal strings */
+
 /* ===========================================================================
  * Check that the match at match_start is indeed a match.
  */
diff --git a/source4/lib/zlib/gzio.c b/source4/lib/zlib/gzio.c
index 7e90f4928f..0b51297936 100644
--- a/source4/lib/zlib/gzio.c
+++ b/source4/lib/zlib/gzio.c
@@ -7,8 +7,6 @@
 
 /* @(#) $Id$ */
 
-#include <stdio.h>
-
 #include "zutil.h"
 
 #ifdef NO_DEFLATE       /* for compatibility with old definition */
@@ -46,7 +44,7 @@ extern void   free   OF((voidpf ptr));
 static int const gz_magic[2] = {0x1f, 0x8b}; /* gzip magic header */
 
 /* gzip flag byte */
-#define ASCII_FLAG   0x01 /* bit 0 set: file probably ascii text */
+/*#define ASCII_FLAG   0x01 *//* bit 0 set: file probably ascii text */
 #define HEAD_CRC     0x02 /* bit 1 set: header CRC present */
 #define EXTRA_FIELD  0x04 /* bit 2 set: extra field present */
 #define ORIG_NAME    0x08 /* bit 3 set: original file name present */
@@ -98,7 +96,7 @@ local gzFile gz_open (path, mode, fd)
     int err;
     int level = Z_DEFAULT_COMPRESSION; /* compression level */
     int strategy = Z_DEFAULT_STRATEGY; /* compression strategy */
-    char *p = (char*)mode;
+    const char *p = mode;
     gz_stream *s;
     char fmode[80]; /* copy of mode, without the compression level */
     char *m = fmode;
@@ -565,7 +563,7 @@ int ZEXPORT gzwrite (file, buf, len)
 
     if (s == NULL || s->mode != 'w') return Z_STREAM_ERROR;
 
-    s->stream.next_in = (Bytef*)buf;
+    s->stream.next_in = (const Bytef*)buf;
     s->stream.avail_in = len;
 
     while (s->stream.avail_in != 0) {
@@ -694,7 +692,7 @@ int ZEXPORT gzputs(file, s)
     gzFile file;
     const char *s;
 {
-    return gzwrite(file, (char*)s, (unsigned)strlen(s));
+    return gzwrite(file, (voidpc)s, (unsigned)strlen(s));
 }
 
 
@@ -988,7 +986,7 @@ const char * ZEXPORT gzerror (file, errnum)
     gzFile file;
     int *errnum;
 {
-    char *m;
+    const char *m;
     gz_stream *s = (gz_stream*)file;
 
     if (s == NULL) {
@@ -998,9 +996,9 @@ const char * ZEXPORT gzerror (file, errnum)
     *errnum = s->z_err;
     if (*errnum == Z_OK) return (const char*)"";
 
-    m = (char*)(*errnum == Z_ERRNO ? zstrerror(errno) : s->stream.msg);
+    m = (*errnum == Z_ERRNO ? zstrerror(errno) : s->stream.msg);
 
-    if (m == NULL || *m == '\0') m = (char*)ERR_MSG(s->z_err);
+    if (m == NULL || *m == '\0') m = ERR_MSG(s->z_err);
 
     TRYFREE(s->msg);
     s->msg = (char*)ALLOC(strlen(s->path) + strlen(m) + 3);
diff --git a/source4/lib/zlib/infback.c b/source4/lib/zlib/infback.c
index 455dbc9ee8..5680937f34 100644
--- a/source4/lib/zlib/infback.c
+++ b/source4/lib/zlib/infback.c
@@ -246,7 +246,7 @@ out_func out;
 void FAR *out_desc;
 {
     struct inflate_state FAR *state;
-    unsigned char FAR *next;    /* next input */
+    unsigned const char FAR *next; /* next input */
     unsigned char FAR *put;     /* next output */
     unsigned have, left;        /* available input and output */
     unsigned long hold;         /* bit buffer */
@@ -308,7 +308,7 @@ void FAR *out_desc;
                 state->mode = TABLE;
                 break;
             case 3:
-                strm->msg = (char *)"invalid block type";
+                strm->msg = "invalid block type";
                 state->mode = BAD;
             }
             DROPBITS(2);
@@ -319,7 +319,7 @@ void FAR *out_desc;
             BYTEBITS();                         /* go to byte boundary */
             NEEDBITS(32);
             if ((hold & 0xffff) != ((hold >> 16) ^ 0xffff)) {
-                strm->msg = (char *)"invalid stored block lengths";
+                strm->msg = "invalid stored block lengths";
                 state->mode = BAD;
                 break;
             }
@@ -357,7 +357,7 @@ void FAR *out_desc;
             DROPBITS(4);
 #ifndef PKZIP_BUG_WORKAROUND
             if (state->nlen > 286 || state->ndist > 30) {
-                strm->msg = (char *)"too many length or distance symbols";
+                strm->msg = "too many length or distance symbols";
                 state->mode = BAD;
                 break;
             }
@@ -379,7 +379,7 @@ void FAR *out_desc;
             ret = inflate_table(CODES, state->lens, 19, &(state->next),
                                 &(state->lenbits), state->work);
             if (ret) {
-                strm->msg = (char *)"invalid code lengths set";
+                strm->msg = "invalid code lengths set";
                 state->mode = BAD;
                 break;
             }
@@ -403,7 +403,7 @@ void FAR *out_desc;
                         NEEDBITS(this.bits + 2);
                         DROPBITS(this.bits);
                         if (state->have == 0) {
-                            strm->msg = (char *)"invalid bit length repeat";
+                            strm->msg = "invalid bit length repeat";
                             state->mode = BAD;
                             break;
                         }
@@ -426,7 +426,7 @@ void FAR *out_desc;
                         DROPBITS(7);
                     }
                     if (state->have + copy > state->nlen + state->ndist) {
-                        strm->msg = (char *)"invalid bit length repeat";
+                        strm->msg = "invalid bit length repeat";
                         state->mode = BAD;
                         break;
                     }
@@ -445,7 +445,7 @@ void FAR *out_desc;
             ret = inflate_table(LENS, state->lens, state->nlen, &(state->next),
                                 &(state->lenbits), state->work);
             if (ret) {
-                strm->msg = (char *)"invalid literal/lengths set";
+                strm->msg = "invalid literal/lengths set";
                 state->mode = BAD;
                 break;
             }
@@ -454,7 +454,7 @@ void FAR *out_desc;
             ret = inflate_table(DISTS, state->lens + state->nlen, state->ndist,
                             &(state->next), &(state->distbits), state->work);
             if (ret) {
-                strm->msg = (char *)"invalid distances set";
+                strm->msg = "invalid distances set";
                 state->mode = BAD;
                 break;
             }
@@ -512,7 +512,7 @@ void FAR *out_desc;
 
             /* invalid code */
             if (this.op & 64) {
-                strm->msg = (char *)"invalid literal/length code";
+                strm->msg = "invalid literal/length code";
                 state->mode = BAD;
                 break;
             }
@@ -544,7 +544,7 @@ void FAR *out_desc;
             }
             DROPBITS(this.bits);
             if (this.op & 64) {
-                strm->msg = (char *)"invalid distance code";
+                strm->msg = "invalid distance code";
                 state->mode = BAD;
                 break;
             }
@@ -559,7 +559,7 @@ void FAR *out_desc;
             }
             if (state->offset > state->wsize - (state->whave < state->wsize ?
                                                 left : 0)) {
-                strm->msg = (char *)"invalid distance too far back";
+                strm->msg = "invalid distance too far back";
                 state->mode = BAD;
                 break;
             }
diff --git a/source4/lib/zlib/inffast.c b/source4/lib/zlib/inffast.c
index bbee92ed1e..bfc727694a 100644
--- a/source4/lib/zlib/inffast.c
+++ b/source4/lib/zlib/inffast.c
@@ -69,8 +69,8 @@ z_streamp strm;
 unsigned start;         /* inflate()'s starting value for strm->avail_out */
 {
     struct inflate_state FAR *state;
-    unsigned char FAR *in;      /* local strm->next_in */
-    unsigned char FAR *last;    /* while in < last, enough input available */
+    unsigned const char FAR *in;   /* local strm->next_in */
+    unsigned const char FAR *last; /* while in < last, enough input available */
     unsigned char FAR *out;     /* local strm->next_out */
     unsigned char FAR *beg;     /* inflate()'s initial strm->next_out */
     unsigned char FAR *end;     /* while out < end, enough space available */
@@ -187,7 +187,7 @@ unsigned start;         /* inflate()'s starting value for strm->avail_out */
                 if (dist > op) {                /* see if copy from window */
                     op = dist - op;             /* distance back in window */
                     if (op > whave) {
-                        strm->msg = (char *)"invalid distance too far back";
+                        strm->msg = "invalid distance too far back";
                         state->mode = BAD;
                         break;
                     }
@@ -263,7 +263,7 @@ unsigned start;         /* inflate()'s starting value for strm->avail_out */
                 goto dodist;
             }
             else {
-                strm->msg = (char *)"invalid distance code";
+                strm->msg = "invalid distance code";
                 state->mode = BAD;
                 break;
             }
@@ -278,7 +278,7 @@ unsigned start;         /* inflate()'s starting value for strm->avail_out */
             break;
         }
         else {
-            strm->msg = (char *)"invalid literal/length code";
+            strm->msg = "invalid literal/length code";
             state->mode = BAD;
             break;
         }
diff --git a/source4/lib/zlib/inflate.c b/source4/lib/zlib/inflate.c
index 0c1ff17951..fbecefd8f5 100644
--- a/source4/lib/zlib/inflate.c
+++ b/source4/lib/zlib/inflate.c
@@ -97,7 +97,7 @@ local int updatewindow OF((z_streamp strm, unsigned out));
 #ifdef BUILDFIXED
    void makefixed OF((void));
 #endif
-local unsigned syncsearch OF((unsigned FAR *have, unsigned char FAR *buf,
+local unsigned syncsearch OF((unsigned FAR *have, unsigned const char FAR *buf,
                               unsigned len));
 
 int ZEXPORT inflateReset2(strm, flags)
@@ -565,7 +565,7 @@ z_streamp strm;
 int flush;
 {
     struct inflate_state FAR *state;
-    unsigned char FAR *next;    /* next input */
+    unsigned const char FAR *next;    /* next input */
     unsigned char FAR *put;     /* next output */
     unsigned have, left;        /* available input and output */
     unsigned long hold;         /* bit buffer */
@@ -617,19 +617,19 @@ int flush;
             if (
 #endif
                 ((BITS(8) << 8) + (hold >> 8)) % 31) {
-                strm->msg = (char *)"incorrect header check";
+                strm->msg = "incorrect header check";
                 state->mode = BAD;
                 break;
             }
             if (BITS(4) != Z_DEFLATED) {
-                strm->msg = (char *)"unknown compression method";
+                strm->msg = "unknown compression method";
                 state->mode = BAD;
                 break;
             }
             DROPBITS(4);
             len = BITS(4) + 8;
             if (len > state->wbits) {
-                strm->msg = (char *)"invalid window size";
+                strm->msg = "invalid window size";
                 state->mode = BAD;
                 break;
             }
@@ -644,12 +644,12 @@ int flush;
             NEEDBITS(16);
             state->flags = (int)(hold);
             if ((state->flags & 0xff) != Z_DEFLATED) {
-                strm->msg = (char *)"unknown compression method";
+                strm->msg = "unknown compression method";
                 state->mode = BAD;
                 break;
             }
             if (state->flags & 0xe000) {
-                strm->msg = (char *)"unknown header flags set";
+                strm->msg = "unknown header flags set";
                 state->mode = BAD;
                 break;
             }
@@ -753,7 +753,7 @@ int flush;
             if (state->flags & 0x0200) {
                 NEEDBITS(16);
                 if (hold != (state->check & 0xffff)) {
-                    strm->msg = (char *)"header crc mismatch";
+                    strm->msg = "header crc mismatch";
                     state->mode = BAD;
                     break;
                 }
@@ -808,7 +808,7 @@ int flush;
                 state->mode = TABLE;
                 break;
             case 3:
-                strm->msg = (char *)"invalid block type";
+                strm->msg = "invalid block type";
                 state->mode = BAD;
             }
             DROPBITS(2);
@@ -817,7 +817,7 @@ int flush;
             BYTEBITS();                         /* go to byte boundary */
             NEEDBITS(32);
             if ((hold & 0xffff) != ((hold >> 16) ^ 0xffff)) {
-                strm->msg = (char *)"invalid stored block lengths";
+                strm->msg = "invalid stored block lengths";
                 state->mode = BAD;
                 break;
             }
@@ -853,7 +853,7 @@ int flush;
             DROPBITS(4);
 #ifndef PKZIP_BUG_WORKAROUND
             if (state->nlen > 286 || state->ndist > 30) {
-                strm->msg = (char *)"too many length or distance symbols";
+                strm->msg = "too many length or distance symbols";
                 state->mode = BAD;
                 break;
             }
@@ -875,7 +875,7 @@ int flush;
             ret = inflate_table(CODES, state->lens, 19, &(state->next),
                                 &(state->lenbits), state->work);
             if (ret) {
-                strm->msg = (char *)"invalid code lengths set";
+                strm->msg = "invalid code lengths set";
                 state->mode = BAD;
                 break;
             }
@@ -899,7 +899,7 @@ int flush;
                         NEEDBITS(this.bits + 2);
                         DROPBITS(this.bits);
                         if (state->have == 0) {
-                            strm->msg = (char *)"invalid bit length repeat";
+                            strm->msg = "invalid bit length repeat";
                             state->mode = BAD;
                             break;
                         }
@@ -922,7 +922,7 @@ int flush;
                         DROPBITS(7);
                     }
                     if (state->have + copy > state->nlen + state->ndist) {
-                        strm->msg = (char *)"invalid bit length repeat";
+                        strm->msg = "invalid bit length repeat";
                         state->mode = BAD;
                         break;
                     }
@@ -941,7 +941,7 @@ int flush;
             ret = inflate_table(LENS, state->lens, state->nlen, &(state->next),
                                 &(state->lenbits), state->work);
             if (ret) {
-                strm->msg = (char *)"invalid literal/lengths set";
+                strm->msg = "invalid literal/lengths set";
                 state->mode = BAD;
                 break;
             }
@@ -950,7 +950,7 @@ int flush;
             ret = inflate_table(DISTS, state->lens + state->nlen, state->ndist,
                             &(state->next), &(state->distbits), state->work);
             if (ret) {
-                strm->msg = (char *)"invalid distances set";
+                strm->msg = "invalid distances set";
                 state->mode = BAD;
                 break;
             }
@@ -993,7 +993,7 @@ int flush;
                 break;
             }
             if (this.op & 64) {
-                strm->msg = (char *)"invalid literal/length code";
+                strm->msg = "invalid literal/length code";
                 state->mode = BAD;
                 break;
             }
@@ -1025,7 +1025,7 @@ int flush;
             }
             DROPBITS(this.bits);
             if (this.op & 64) {
-                strm->msg = (char *)"invalid distance code";
+                strm->msg = "invalid distance code";
                 state->mode = BAD;
                 break;
             }
@@ -1040,13 +1040,13 @@ int flush;
             }
 #ifdef INFLATE_STRICT
             if (state->offset > state->dmax) {
-                strm->msg = (char *)"invalid distance too far back";
+                strm->msg = "invalid distance too far back";
                 state->mode = BAD;
                 break;
             }
 #endif
             if (state->offset > state->whave + out - left) {
-                strm->msg = (char *)"invalid distance too far back";
+                strm->msg = "invalid distance too far back";
                 state->mode = BAD;
                 break;
             }
@@ -1098,7 +1098,7 @@ int flush;
                      state->flags ? hold :
 #endif
                      REVERSE(hold)) != state->check) {
-                    strm->msg = (char *)"incorrect data check";
+                    strm->msg = "incorrect data check";
                     state->mode = BAD;
                     break;
                 }
@@ -1111,7 +1111,7 @@ int flush;
             if (state->wrap && state->flags) {
                 NEEDBITS(32);
                 if (hold != (state->total & 0xffffffffUL)) {
-                    strm->msg = (char *)"incorrect length check";
+                    strm->msg = "incorrect length check";
                     state->mode = BAD;
                     break;
                 }
@@ -1247,7 +1247,7 @@ gz_headerp head;
  */
 local unsigned syncsearch(have, buf, len)
 unsigned FAR *have;
-unsigned char FAR *buf;
+unsigned const char FAR *buf;
 unsigned len;
 {
     unsigned got;
diff --git a/source4/lib/zlib/trees.c b/source4/lib/zlib/trees.c
index 395e4e1681..eb55679adc 100644
--- a/source4/lib/zlib/trees.c
+++ b/source4/lib/zlib/trees.c
@@ -150,8 +150,8 @@ local void send_tree      OF((deflate_state *s, ct_data *tree, int max_code));
 local int  build_bl_tree  OF((deflate_state *s));
 local void send_all_trees OF((deflate_state *s, int lcodes, int dcodes,
                               int blcodes));
-local void compress_block OF((deflate_state *s, ct_data *ltree,
-                              ct_data *dtree));
+local void compress_block OF((deflate_state *s, const ct_data *ltree,
+                              const ct_data *dtree));
 local void set_data_type  OF((deflate_state *s));
 local unsigned bi_reverse OF((unsigned value, int length));
 local void bi_windup      OF((deflate_state *s));
@@ -986,7 +986,7 @@ void _tr_flush_block(s, buf, stored_len, eof)
     } else if (s->strategy == Z_FIXED || static_lenb == opt_lenb) {
 #endif
         send_bits(s, (STATIC_TREES<<1)+eof, 3);
-        compress_block(s, (ct_data *)static_ltree, (ct_data *)static_dtree);
+        compress_block(s, static_ltree, static_dtree);
 #ifdef DEBUG
         s->compressed_len += 3 + s->static_len;
 #endif
@@ -994,7 +994,7 @@ void _tr_flush_block(s, buf, stored_len, eof)
         send_bits(s, (DYN_TREES<<1)+eof, 3);
         send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1,
                        max_blindex+1);
-        compress_block(s, (ct_data *)s->dyn_ltree, (ct_data *)s->dyn_dtree);
+        compress_block(s, s->dyn_ltree, s->dyn_dtree);
 #ifdef DEBUG
         s->compressed_len += 3 + s->opt_len;
 #endif
@@ -1071,8 +1071,8 @@ int _tr_tally (s, dist, lc)
  */
 local void compress_block(s, ltree, dtree)
     deflate_state *s;
-    ct_data *ltree; /* literal tree */
-    ct_data *dtree; /* distance tree */
+    const ct_data *ltree; /* literal tree */
+    const ct_data *dtree; /* distance tree */
 {
     unsigned dist;      /* distance of matched string */
     int lc;             /* match length or unmatched char (if dist == 0) */
diff --git a/source4/lib/zlib/uncompr.c b/source4/lib/zlib/uncompr.c
index b59e3d0def..a052f22e74 100644
--- a/source4/lib/zlib/uncompr.c
+++ b/source4/lib/zlib/uncompr.c
@@ -5,8 +5,7 @@
 
 /* @(#) $Id$ */
 
-#define ZLIB_INTERNAL
-#include "zlib.h"
+#include "zutil.h"
 
 /* ===========================================================================
      Decompresses the source buffer into the destination buffer.  sourceLen is
@@ -32,7 +31,7 @@ int ZEXPORT uncompress (dest, destLen, source, sourceLen)
     z_stream stream;
     int err;
 
-    stream.next_in = (Bytef*)source;
+    stream.next_in = source;
     stream.avail_in = (uInt)sourceLen;
     /* Check for source > 64K on 16-bit machine: */
     if ((uLong)stream.avail_in != sourceLen) return Z_BUF_ERROR;
diff --git a/source4/lib/zlib/zlib.h b/source4/lib/zlib/zlib.h
index e80eed9a7e..5549f9cf57 100644
--- a/source4/lib/zlib/zlib.h
+++ b/source4/lib/zlib/zlib.h
@@ -80,7 +80,7 @@ typedef void   (*free_func)  OF((voidpf opaque, voidpf address));
 struct internal_state;
 
 typedef struct z_stream_s {
-    Bytef    *next_in;  /* next input byte */
+    const Bytef *next_in; /* next input byte */
     uInt     avail_in;  /* number of bytes available at next_in */
     uLong    total_in;  /* total nb of input bytes read so far */
 
@@ -88,7 +88,7 @@ typedef struct z_stream_s {
     uInt     avail_out; /* remaining free space at next_out */
     uLong    total_out; /* total nb of bytes output so far */
 
-    char     *msg;      /* last error message, NULL if no error */
+    const char    *msg; /* last error message, NULL if no error */
     struct internal_state FAR *state; /* not visible by applications */
 
     alloc_func zalloc;  /* used to allocate the internal state */
@@ -210,6 +210,16 @@ typedef gz_header FAR *gz_headerp;
 #define zlib_version zlibVersion()
 /* for compatibility with versions < 1.0.2 */
 
+#if (__GNUC__ >= 3) && (__GNUC_MINOR__ >= 1)
+/** Use gcc attribute to check printf fns.  a1 is the 1-based index of
+ * the parameter containing the format, and a2 the index of the first
+ * argument. Note that some gcc 2.x versions don't handle this
+ * properly **/
+#define _Z_PRINTF_ATTRIBUTE(a1, a2) __attribute__ ((format (__printf__, a1, a2)))
+#else
+#define _Z_PRINTF_ATTRIBUTE(a1, a2)
+#endif
+
                         /* basic functions */
 
 ZEXTERN const char * ZEXPORT zlibVersion OF((void));
@@ -887,7 +897,7 @@ ZEXTERN int ZEXPORT inflateBackInit OF((z_streamp strm, int windowBits,
    match the version of the header file.
 */
 
-typedef unsigned (*in_func) OF((void FAR *, unsigned char FAR * FAR *));
+typedef unsigned (*in_func) OF((void FAR *, unsigned const char FAR * FAR *));
 typedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned));
 
 ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
@@ -1132,7 +1142,8 @@ ZEXTERN int ZEXPORT    gzwrite OF((gzFile file,
    (0 in case of error).
 */
 
-ZEXTERN int ZEXPORTVA   gzprintf OF((gzFile file, const char *format, ...));
+ZEXTERN int ZEXPORTVA   gzprintf OF((gzFile file, const char *format, ...))
+				    _Z_PRINTF_ATTRIBUTE(2, 3);
 /*
      Converts, formats, and writes the args to the compressed file under
    control of the format string, as in fprintf. gzprintf returns the number of
diff --git a/source4/lib/zlib/zutil.h b/source4/lib/zlib/zutil.h
index b7d5eff81b..edd8e0acbb 100644
--- a/source4/lib/zlib/zutil.h
+++ b/source4/lib/zlib/zutil.h
@@ -56,7 +56,7 @@ extern const char * const z_errmsg[10]; /* indexed by 2-zlib_error */
 #define ERR_MSG(err) z_errmsg[Z_NEED_DICT-(err)]
 
 #define ERR_RETURN(strm,err) \
-  return (strm->msg = (char*)ERR_MSG(err), (err))
+  return (strm->msg = ERR_MSG(err), (err))
 /* To be used only when the state is known to be valid */
 
         /* common constants */