Issue #18527: Upgrade internal copy of zlib to 1.2.8

1 files changed, 378 insertions, 143 deletions

diff --git a/Modules/zlib/configure b/Modules/zlib/configure
index bd9edd2..b77a8a8 100755
--- a/Modules/zlib/configure
+++ b/Modules/zlib/configure
@@ -13,39 +13,52 @@
 # If you have problems, try without defining CC and CFLAGS before reporting
 # an error.
 
+# start off configure.log
+echo -------------------- >> configure.log
+echo $0 $* >> configure.log
+date >> configure.log
+
+# set command prefix for cross-compilation
 if [ -n "${CHOST}" ]; then
-    uname="$(echo "${CHOST}" | sed -e 's/^[^-]*-\([^-]*\)$/\1/' -e 's/^[^-]*-[^-]*-\([^-]*\)$/\1/' -e 's/^[^-]*-[^-]*-\([^-]*\)-.*$/\1/')"
+    uname="`echo "${CHOST}" | sed -e 's/^[^-]*-\([^-]*\)$/\1/' -e 's/^[^-]*-[^-]*-\([^-]*\)$/\1/' -e 's/^[^-]*-[^-]*-\([^-]*\)-.*$/\1/'`"
     CROSS_PREFIX="${CHOST}-"
 fi
 
+# destination name for static library
 STATICLIB=libz.a
-LDFLAGS="${LDFLAGS} -L. ${STATICLIB}"
+
+# extract zlib version numbers from zlib.h
 VER=`sed -n -e '/VERSION "/s/.*"\(.*\)".*/\1/p' < zlib.h`
 VER3=`sed -n -e '/VERSION "/s/.*"\([0-9]*\\.[0-9]*\\.[0-9]*\).*/\1/p' < zlib.h`
 VER2=`sed -n -e '/VERSION "/s/.*"\([0-9]*\\.[0-9]*\)\\..*/\1/p' < zlib.h`
 VER1=`sed -n -e '/VERSION "/s/.*"\([0-9]*\)\\..*/\1/p' < zlib.h`
+
+# establish commands for library building
 if "${CROSS_PREFIX}ar" --version >/dev/null 2>/dev/null || test $? -lt 126; then
     AR=${AR-"${CROSS_PREFIX}ar"}
-    test -n "${CROSS_PREFIX}" && echo Using ${AR}
+    test -n "${CROSS_PREFIX}" && echo Using ${AR} | tee -a configure.log
 else
     AR=${AR-"ar"}
-    test -n "${CROSS_PREFIX}" && echo Using ${AR}
+    test -n "${CROSS_PREFIX}" && echo Using ${AR} | tee -a configure.log
 fi
-AR_RC="${AR} rc"
+ARFLAGS=${ARFLAGS-"rc"}
 if "${CROSS_PREFIX}ranlib" --version >/dev/null 2>/dev/null || test $? -lt 126; then
     RANLIB=${RANLIB-"${CROSS_PREFIX}ranlib"}
-    test -n "${CROSS_PREFIX}" && echo Using ${RANLIB}
+    test -n "${CROSS_PREFIX}" && echo Using ${RANLIB} | tee -a configure.log
 else
     RANLIB=${RANLIB-"ranlib"}
 fi
 if "${CROSS_PREFIX}nm" --version >/dev/null 2>/dev/null || test $? -lt 126; then
     NM=${NM-"${CROSS_PREFIX}nm"}
-    test -n "${CROSS_PREFIX}" && echo Using ${NM}
+    test -n "${CROSS_PREFIX}" && echo Using ${NM} | tee -a configure.log
 else
     NM=${NM-"nm"}
 fi
+
+# set defaults before processing command line options
 LDCONFIG=${LDCONFIG-"ldconfig"}
 LDSHAREDLIBC="${LDSHAREDLIBC--lc}"
+ARCHS=
 prefix=${prefix-/usr/local}
 exec_prefix=${exec_prefix-'${prefix}'}
 libdir=${libdir-'${exec_prefix}/lib'}
@@ -54,20 +67,39 @@ includedir=${includedir-'${prefix}/include'}
 mandir=${mandir-'${prefix}/share/man'}
 shared_ext='.so'
 shared=1
+solo=0
+cover=0
 zprefix=0
+zconst=0
 build64=0
 gcc=0
 old_cc="$CC"
 old_cflags="$CFLAGS"
+OBJC='$(OBJZ) $(OBJG)'
+PIC_OBJC='$(PIC_OBJZ) $(PIC_OBJG)'
+
+# leave this script, optionally in a bad way
+leave()
+{
+  if test "$*" != "0"; then
+    echo "** $0 aborting." | tee -a configure.log
+  fi
+  rm -f $test.[co] $test $test$shared_ext $test.gcno ./--version
+  echo -------------------- >> configure.log
+  echo >> configure.log
+  echo >> configure.log
+  exit $1
+}
 
+# process command line options
 while test $# -ge 1
 do
 case "$1" in
     -h* | --help)
-      echo 'usage:'
-      echo '  configure [--zprefix] [--prefix=PREFIX]  [--eprefix=EXPREFIX]'
-      echo '    [--static] [--64] [--libdir=LIBDIR] [--sharedlibdir=LIBDIR]'
-      echo '    [--includedir=INCLUDEDIR]'
+      echo 'usage:' | tee -a configure.log
+      echo '  configure [--const] [--zprefix] [--prefix=PREFIX]  [--eprefix=EXPREFIX]' | tee -a configure.log
+      echo '    [--static] [--64] [--libdir=LIBDIR] [--sharedlibdir=LIBDIR]' | tee -a configure.log
+      echo '    [--includedir=INCLUDEDIR] [--archs="-arch i386 -arch x86_64"]' | tee -a configure.log
         exit 0 ;;
     -p*=* | --prefix=*) prefix=`echo $1 | sed 's/.*=//'`; shift ;;
     -e*=* | --eprefix=*) exec_prefix=`echo $1 | sed 's/.*=//'`; shift ;;
@@ -81,51 +113,88 @@ case "$1" in
     -i* | --includedir) includedir="$2"; shift; shift ;;
     -s* | --shared | --enable-shared) shared=1; shift ;;
     -t | --static) shared=0; shift ;;
+    --solo) solo=1; shift ;;
+    --cover) cover=1; shift ;;
     -z* | --zprefix) zprefix=1; shift ;;
     -6* | --64) build64=1; shift ;;
-    --sysconfdir=*) echo "ignored option: --sysconfdir"; shift ;;
-    --localstatedir=*) echo "ignored option: --localstatedir"; shift ;;
-    *) echo "unknown option: $1"; echo "$0 --help for help"; exit 1 ;;
+    -a*=* | --archs=*) ARCHS=`echo $1 | sed 's/.*=//'`; shift ;;
+    --sysconfdir=*) echo "ignored option: --sysconfdir" | tee -a configure.log; shift ;;
+    --localstatedir=*) echo "ignored option: --localstatedir" | tee -a configure.log; shift ;;
+    -c* | --const) zconst=1; shift ;;
+    *)
+      echo "unknown option: $1" | tee -a configure.log
+      echo "$0 --help for help" | tee -a configure.log
+      leave 1;;
     esac
 done
 
+# temporary file name
 test=ztest$$
+
+# put arguments in log, also put test file in log if used in arguments
+show()
+{
+  case "$*" in
+    *$test.c*)
+      echo === $test.c === >> configure.log
+      cat $test.c >> configure.log
+      echo === >> configure.log;;
+  esac
+  echo $* >> configure.log
+}
+
+# check for gcc vs. cc and set compile and link flags based on the system identified by uname
 cat > $test.c <<EOF
 extern int getchar();
 int hello() {return getchar();}
 EOF
 
-test -z "$CC" && echo Checking for ${CROSS_PREFIX}gcc...
+test -z "$CC" && echo Checking for ${CROSS_PREFIX}gcc... | tee -a configure.log
 cc=${CC-${CROSS_PREFIX}gcc}
 cflags=${CFLAGS-"-O3"}
 # to force the asm version use: CFLAGS="-O3 -DASMV" ./configure
 case "$cc" in
   *gcc*) gcc=1 ;;
+  *clang*) gcc=1 ;;
+esac
+case `$cc -v 2>&1` in
+  *gcc*) gcc=1 ;;
 esac
 
-if test "$gcc" -eq 1 && ($cc -c $cflags $test.c) 2>/dev/null; then
+show $cc -c $test.c
+if test "$gcc" -eq 1 && ($cc -c $test.c) >> configure.log 2>&1; then
+  echo ... using gcc >> configure.log
   CC="$cc"
+  CFLAGS="${CFLAGS--O3} ${ARCHS}"
   SFLAGS="${CFLAGS--O3} -fPIC"
-  CFLAGS="${CFLAGS--O3}"
+  LDFLAGS="${LDFLAGS} ${ARCHS}"
   if test $build64 -eq 1; then
     CFLAGS="${CFLAGS} -m64"
     SFLAGS="${SFLAGS} -m64"
   fi
   if test "${ZLIBGCCWARN}" = "YES"; then
-    CFLAGS="${CFLAGS} -Wall -Wextra -pedantic"
+    if test "$zconst" -eq 1; then
+      CFLAGS="${CFLAGS} -Wall -Wextra -Wcast-qual -pedantic -DZLIB_CONST"
+    else
+      CFLAGS="${CFLAGS} -Wall -Wextra -pedantic"
+    fi
   fi
   if test -z "$uname"; then
     uname=`(uname -s || echo unknown) 2>/dev/null`
   fi
   case "$uname" in
-  Linux* | linux* | GNU | GNU/* | *BSD | DragonFly) LDSHARED=${LDSHARED-"$cc -shared -Wl,-soname,libz.so.1,--version-script,zlib.map"} ;;
+  Linux* | linux* | GNU | GNU/* | solaris*)
+        LDSHARED=${LDSHARED-"$cc -shared -Wl,-soname,libz.so.1,--version-script,zlib.map"} ;;
+  *BSD | *bsd* | DragonFly)
+        LDSHARED=${LDSHARED-"$cc -shared -Wl,-soname,libz.so.1,--version-script,zlib.map"}
+        LDCONFIG="ldconfig -m" ;;
   CYGWIN* | Cygwin* | cygwin* | OS/2*)
         EXE='.exe' ;;
-  MINGW*|mingw*)
+  MINGW* | mingw*)
 # temporary bypass
         rm -f $test.[co] $test $test$shared_ext
-        echo "Please use win32/Makefile.gcc instead."
-        exit 1
+        echo "Please use win32/Makefile.gcc instead." | tee -a configure.log
+        leave 1
         LDSHARED=${LDSHARED-"$cc -shared"}
         LDSHAREDLIBC=""
         EXE='.exe' ;;
@@ -142,17 +211,25 @@ if test "$gcc" -eq 1 && ($cc -c $cflags $test.c) 2>/dev/null; then
                  shared_ext='.sl'
                  SHAREDLIB='libz.sl' ;;
          esac ;;
-  Darwin*)   shared_ext='.dylib'
+  Darwin* | darwin*)
+             shared_ext='.dylib'
              SHAREDLIB=libz$shared_ext
              SHAREDLIBV=libz.$VER$shared_ext
              SHAREDLIBM=libz.$VER1$shared_ext
-             LDSHARED=${LDSHARED-"$cc -dynamiclib -install_name $libdir/$SHAREDLIBM -compatibility_version $VER1 -current_version $VER3"} ;;
+             LDSHARED=${LDSHARED-"$cc -dynamiclib -install_name $libdir/$SHAREDLIBM -compatibility_version $VER1 -current_version $VER3"}
+             if libtool -V 2>&1 | grep Apple > /dev/null; then
+                 AR="libtool"
+             else
+                 AR="/usr/bin/libtool"
+             fi
+             ARFLAGS="-o" ;;
   *)             LDSHARED=${LDSHARED-"$cc -shared"} ;;
   esac
 else
   # find system name and corresponding cc options
   CC=${CC-cc}
   gcc=0
+  echo ... using $CC >> configure.log
   if test -z "$uname"; then
     uname=`(uname -sr || echo unknown) 2>/dev/null`
   fi
@@ -183,19 +260,34 @@ else
              CFLAGS=${CFLAGS-"-4 -O"}
              LDSHARED=${LDSHARED-"cc"}
              RANLIB=${RANLIB-"true"}
-             AR_RC="cc -A" ;;
+             AR="cc"
+             ARFLAGS="-A" ;;
   SCO_SV\ 3.2*) SFLAGS=${CFLAGS-"-O3 -dy -KPIC "}
              CFLAGS=${CFLAGS-"-O3"}
              LDSHARED=${LDSHARED-"cc -dy -KPIC -G"} ;;
-  SunOS\ 5*) LDSHARED=${LDSHARED-"cc -G"}
-         case `(uname -m || echo unknown) 2>/dev/null` in
-         i86*)
-             SFLAGS=${CFLAGS-"-xpentium -fast -KPIC -R."}
-             CFLAGS=${CFLAGS-"-xpentium -fast"} ;;
-         *)
-             SFLAGS=${CFLAGS-"-fast -xcg92 -KPIC -R."}
-             CFLAGS=${CFLAGS-"-fast -xcg92"} ;;
-         esac ;;
+  SunOS\ 5* | solaris*)
+         LDSHARED=${LDSHARED-"cc -G -h libz$shared_ext.$VER1"}
+         SFLAGS=${CFLAGS-"-fast -KPIC"}
+         CFLAGS=${CFLAGS-"-fast"}
+         if test $build64 -eq 1; then
+             # old versions of SunPRO/Workshop/Studio don't support -m64,
+             # but newer ones do.  Check for it.
+             flag64=`$CC -flags | egrep -- '^-m64'`
+             if test x"$flag64" != x"" ; then
+                 CFLAGS="${CFLAGS} -m64"
+                 SFLAGS="${SFLAGS} -m64"
+             else
+                 case `(uname -m || echo unknown) 2>/dev/null` in
+                   i86*)
+                     SFLAGS="$SFLAGS -xarch=amd64"
+                     CFLAGS="$CFLAGS -xarch=amd64" ;;
+                   *)
+                     SFLAGS="$SFLAGS -xarch=v9"
+                     CFLAGS="$CFLAGS -xarch=v9" ;;
+                 esac
+             fi
+         fi
+         ;;
   SunOS\ 4*) SFLAGS=${CFLAGS-"-O2 -PIC"}
              CFLAGS=${CFLAGS-"-O2"}
              LDSHARED=${LDSHARED-"ld"} ;;
@@ -225,25 +317,79 @@ else
   esac
 fi
 
+# destination names for shared library if not defined above
 SHAREDLIB=${SHAREDLIB-"libz$shared_ext"}
 SHAREDLIBV=${SHAREDLIBV-"libz$shared_ext.$VER"}
 SHAREDLIBM=${SHAREDLIBM-"libz$shared_ext.$VER1"}
 
+echo >> configure.log
+
+# define functions for testing compiler and library characteristics and logging the results
+
+cat > $test.c <<EOF
+#error error
+EOF
+if ($CC -c $CFLAGS $test.c) 2>/dev/null; then
+  try()
+  {
+    show $*
+    test "`( $* ) 2>&1 | tee -a configure.log`" = ""
+  }
+  echo - using any output from compiler to indicate an error >> configure.log
+else
+try()
+{
+  show $*
+  ( $* ) >> configure.log 2>&1
+  ret=$?
+  if test $ret -ne 0; then
+    echo "(exit code "$ret")" >> configure.log
+  fi
+  return $ret
+}
+fi
+
+tryboth()
+{
+  show $*
+  got=`( $* ) 2>&1`
+  ret=$?
+  printf %s "$got" >> configure.log
+  if test $ret -ne 0; then
+    return $ret
+  fi
+  test "$got" = ""
+}
+
+cat > $test.c << EOF
+int foo() { return 0; }
+EOF
+echo "Checking for obsessive-compulsive compiler options..." >> configure.log
+if try $CC -c $CFLAGS $test.c; then
+  :
+else
+  echo "Compiler error reporting is too harsh for $0 (perhaps remove -Werror)." | tee -a configure.log
+  leave 1
+fi
+
+echo >> configure.log
+
+# see if shared library build supported
+cat > $test.c <<EOF
+extern int getchar();
+int hello() {return getchar();}
+EOF
 if test $shared -eq 1; then
-  echo Checking for shared library support...
+  echo Checking for shared library support... | tee -a configure.log
   # we must test in two steps (cc then ld), required at least on SunOS 4.x
-  if test "`($CC -w -c $SFLAGS $test.c) 2>&1`" = "" &&
-     test "`($LDSHARED $SFLAGS -o $test$shared_ext $test.o) 2>&1`" = ""; then
-    echo Building shared library $SHAREDLIBV with $CC.
+  if try $CC -w -c $SFLAGS $test.c &&
+     try $LDSHARED $SFLAGS -o $test$shared_ext $test.o; then
+    echo Building shared library $SHAREDLIBV with $CC. | tee -a configure.log
   elif test -z "$old_cc" -a -z "$old_cflags"; then
-    echo No shared library support.
+    echo No shared library support. | tee -a configure.log
     shared=0;
   else
-    echo Tested $CC -w -c $SFLAGS $test.c
-    $CC -w -c $SFLAGS $test.c
-    echo Tested $LDSHARED $SFLAGS -o $test$shared_ext $test.o
-    $LDSHARED $SFLAGS -o $test$shared_ext $test.o
-    echo 'No shared library support; try without defining CC and CFLAGS'
+    echo 'No shared library support; try without defining CC and CFLAGS' | tee -a configure.log
     shared=0;
   fi
 fi
@@ -254,25 +400,43 @@ if test $shared -eq 0; then
   SHAREDLIB=""
   SHAREDLIBV=""
   SHAREDLIBM=""
-  echo Building static library $STATICLIB version $VER with $CC.
+  echo Building static library $STATICLIB version $VER with $CC. | tee -a configure.log
 else
   ALL="static shared"
   TEST="all teststatic testshared"
 fi
 
+# check for underscores in external names for use by assembler code
+CPP=${CPP-"$CC -E"}
+case $CFLAGS in
+  *ASMV*)
+    echo >> configure.log
+    show "$NM $test.o | grep _hello"
+    if test "`$NM $test.o | grep _hello | tee -a configure.log`" = ""; then
+      CPP="$CPP -DNO_UNDERLINE"
+      echo Checking for underline in external names... No. | tee -a configure.log
+    else
+      echo Checking for underline in external names... Yes. | tee -a configure.log
+    fi ;;
+esac
+
+echo >> configure.log
+
+# check for large file support, and if none, check for fseeko()
 cat > $test.c <<EOF
 #include <sys/types.h>
 off64_t dummy = 0;
 EOF
-if test "`($CC -c $CFLAGS -D_LARGEFILE64_SOURCE=1 $test.c) 2>&1`" = ""; then
+if try $CC -c $CFLAGS -D_LARGEFILE64_SOURCE=1 $test.c; then
   CFLAGS="${CFLAGS} -D_LARGEFILE64_SOURCE=1"
   SFLAGS="${SFLAGS} -D_LARGEFILE64_SOURCE=1"
   ALL="${ALL} all64"
   TEST="${TEST} test64"
-  echo "Checking for off64_t... Yes."
-  echo "Checking for fseeko... Yes."
+  echo "Checking for off64_t... Yes." | tee -a configure.log
+  echo "Checking for fseeko... Yes." | tee -a configure.log
 else
-  echo "Checking for off64_t... No."
+  echo "Checking for off64_t... No." | tee -a configure.log
+  echo >> configure.log
   cat > $test.c <<EOF
 #include <stdio.h>
 int main(void) {
@@ -280,272 +444,335 @@ int main(void) {
   return 0;
 }
 EOF
-  if test "`($CC $CFLAGS -o $test $test.c) 2>&1`" = ""; then
-    echo "Checking for fseeko... Yes."
+  if try $CC $CFLAGS -o $test $test.c; then
+    echo "Checking for fseeko... Yes." | tee -a configure.log
   else
     CFLAGS="${CFLAGS} -DNO_FSEEKO"
     SFLAGS="${SFLAGS} -DNO_FSEEKO"
-    echo "Checking for fseeko... No."
+    echo "Checking for fseeko... No." | tee -a configure.log
   fi
 fi
 
+echo >> configure.log
+
+# check for strerror() for use by gz* functions
+cat > $test.c <<EOF
+#include <string.h>
+#include <errno.h>
+int main() { return strlen(strerror(errno)); }
+EOF
+if try $CC $CFLAGS -o $test $test.c; then
+  echo "Checking for strerror... Yes." | tee -a configure.log
+else
+  CFLAGS="${CFLAGS} -DNO_STRERROR"
+  SFLAGS="${SFLAGS} -DNO_STRERROR"
+  echo "Checking for strerror... No." | tee -a configure.log
+fi
+
+# copy clean zconf.h for subsequent edits
 cp -p zconf.h.in zconf.h
 
+echo >> configure.log
+
+# check for unistd.h and save result in zconf.h
 cat > $test.c <<EOF
 #include <unistd.h>
 int main() { return 0; }
 EOF
-if test "`($CC -c $CFLAGS $test.c) 2>&1`" = ""; then
+if try $CC -c $CFLAGS $test.c; then
   sed < zconf.h "/^#ifdef HAVE_UNISTD_H.* may be/s/def HAVE_UNISTD_H\(.*\) may be/ 1\1 was/" > zconf.temp.h
   mv zconf.temp.h zconf.h
-  echo "Checking for unistd.h... Yes."
+  echo "Checking for unistd.h... Yes." | tee -a configure.log
+else
+  echo "Checking for unistd.h... No." | tee -a configure.log
+fi
+
+echo >> configure.log
+
+# check for stdarg.h and save result in zconf.h
+cat > $test.c <<EOF
+#include <stdarg.h>
+int main() { return 0; }
+EOF
+if try $CC -c $CFLAGS $test.c; then
+  sed < zconf.h "/^#ifdef HAVE_STDARG_H.* may be/s/def HAVE_STDARG_H\(.*\) may be/ 1\1 was/" > zconf.temp.h
+  mv zconf.temp.h zconf.h
+  echo "Checking for stdarg.h... Yes." | tee -a configure.log
 else
-  echo "Checking for unistd.h... No."
+  echo "Checking for stdarg.h... No." | tee -a configure.log
 fi
 
+# if the z_ prefix was requested, save that in zconf.h
 if test $zprefix -eq 1; then
   sed < zconf.h "/#ifdef Z_PREFIX.* may be/s/def Z_PREFIX\(.*\) may be/ 1\1 was/" > zconf.temp.h
   mv zconf.temp.h zconf.h
-  echo "Using z_ prefix on all symbols."
+  echo >> configure.log
+  echo "Using z_ prefix on all symbols." | tee -a configure.log
 fi
 
+# if --solo compilation was requested, save that in zconf.h and remove gz stuff from object lists
+if test $solo -eq 1; then
+  sed '/#define ZCONF_H/a\
+#define Z_SOLO
+
+' < zconf.h > zconf.temp.h
+  mv zconf.temp.h zconf.h
+OBJC='$(OBJZ)'
+PIC_OBJC='$(PIC_OBJZ)'
+fi
+
+# if code coverage testing was requested, use older gcc if defined, e.g. "gcc-4.2" on Mac OS X
+if test $cover -eq 1; then
+  CFLAGS="${CFLAGS} -fprofile-arcs -ftest-coverage"
+  if test -n "$GCC_CLASSIC"; then
+    CC=$GCC_CLASSIC
+  fi
+fi
+
+echo >> configure.log
+
+# conduct a series of tests to resolve eight possible cases of using "vs" or "s" printf functions
+# (using stdarg or not), with or without "n" (proving size of buffer), and with or without a
+# return value.  The most secure result is vsnprintf() with a return value.  snprintf() with a
+# return value is secure as well, but then gzprintf() will be limited to 20 arguments.
 cat > $test.c <<EOF
 #include <stdio.h>
 #include <stdarg.h>
 #include "zconf.h"
-
 int main()
 {
 #ifndef STDC
   choke me
 #endif
-
   return 0;
 }
 EOF
+if try $CC -c $CFLAGS $test.c; then
+  echo "Checking whether to use vs[n]printf() or s[n]printf()... using vs[n]printf()." | tee -a configure.log
 
-if test "`($CC -c $CFLAGS $test.c) 2>&1`" = ""; then
-  echo "Checking whether to use vs[n]printf() or s[n]printf()... using vs[n]printf()."
-
+  echo >> configure.log
   cat > $test.c <<EOF
 #include <stdio.h>
 #include <stdarg.h>
-
 int mytest(const char *fmt, ...)
 {
   char buf[20];
   va_list ap;
-
   va_start(ap, fmt);
   vsnprintf(buf, sizeof(buf), fmt, ap);
   va_end(ap);
   return 0;
 }
-
 int main()
 {
   return (mytest("Hello%d\n", 1));
 }
 EOF
+  if try $CC $CFLAGS -o $test $test.c; then
+    echo "Checking for vsnprintf() in stdio.h... Yes." | tee -a configure.log
 
-  if test "`($CC $CFLAGS -o $test $test.c) 2>&1`" = ""; then
-    echo "Checking for vsnprintf() in stdio.h... Yes."
-
+    echo >> configure.log
     cat >$test.c <<EOF
 #include <stdio.h>
 #include <stdarg.h>
-
 int mytest(const char *fmt, ...)
 {
   int n;
   char buf[20];
   va_list ap;
-
   va_start(ap, fmt);
   n = vsnprintf(buf, sizeof(buf), fmt, ap);
   va_end(ap);
   return n;
 }
-
 int main()
 {
   return (mytest("Hello%d\n", 1));
 }
 EOF
 
-    if test "`($CC -c $CFLAGS $test.c) 2>&1`" = ""; then
-      echo "Checking for return value of vsnprintf()... Yes."
+    if try $CC -c $CFLAGS $test.c; then
+      echo "Checking for return value of vsnprintf()... Yes." | tee -a configure.log
     else
       CFLAGS="$CFLAGS -DHAS_vsnprintf_void"
       SFLAGS="$SFLAGS -DHAS_vsnprintf_void"
-      echo "Checking for return value of vsnprintf()... No."
-      echo "  WARNING: apparently vsnprintf() does not return a value. zlib"
-      echo "  can build but will be open to possible string-format security"
-      echo "  vulnerabilities."
+      echo "Checking for return value of vsnprintf()... No." | tee -a configure.log
+      echo "  WARNING: apparently vsnprintf() does not return a value. zlib" | tee -a configure.log
+      echo "  can build but will be open to possible string-format security" | tee -a configure.log
+      echo "  vulnerabilities." | tee -a configure.log
     fi
   else
     CFLAGS="$CFLAGS -DNO_vsnprintf"
     SFLAGS="$SFLAGS -DNO_vsnprintf"
-    echo "Checking for vsnprintf() in stdio.h... No."
-    echo "  WARNING: vsnprintf() not found, falling back to vsprintf(). zlib"
-    echo "  can build but will be open to possible buffer-overflow security"
-    echo "  vulnerabilities."
+    echo "Checking for vsnprintf() in stdio.h... No." | tee -a configure.log
+    echo "  WARNING: vsnprintf() not found, falling back to vsprintf(). zlib" | tee -a configure.log
+    echo "  can build but will be open to possible buffer-overflow security" | tee -a configure.log
+    echo "  vulnerabilities." | tee -a configure.log
 
+    echo >> configure.log
     cat >$test.c <<EOF
 #include <stdio.h>
 #include <stdarg.h>
-
 int mytest(const char *fmt, ...)
 {
   int n;
   char buf[20];
   va_list ap;
-
   va_start(ap, fmt);
   n = vsprintf(buf, fmt, ap);
   va_end(ap);
   return n;
 }
-
 int main()
 {
   return (mytest("Hello%d\n", 1));
 }
 EOF
 
-    if test "`($CC -c $CFLAGS $test.c) 2>&1`" = ""; then
-      echo "Checking for return value of vsprintf()... Yes."
+    if try $CC -c $CFLAGS $test.c; then
+      echo "Checking for return value of vsprintf()... Yes." | tee -a configure.log
     else
       CFLAGS="$CFLAGS -DHAS_vsprintf_void"
       SFLAGS="$SFLAGS -DHAS_vsprintf_void"
-      echo "Checking for return value of vsprintf()... No."
-      echo "  WARNING: apparently vsprintf() does not return a value. zlib"
-      echo "  can build but will be open to possible string-format security"
-      echo "  vulnerabilities."
+      echo "Checking for return value of vsprintf()... No." | tee -a configure.log
+      echo "  WARNING: apparently vsprintf() does not return a value. zlib" | tee -a configure.log
+      echo "  can build but will be open to possible string-format security" | tee -a configure.log
+      echo "  vulnerabilities." | tee -a configure.log
     fi
   fi
 else
-  echo "Checking whether to use vs[n]printf() or s[n]printf()... using s[n]printf()."
+  echo "Checking whether to use vs[n]printf() or s[n]printf()... using s[n]printf()." | tee -a configure.log
 
+  echo >> configure.log
   cat >$test.c <<EOF
 #include <stdio.h>
-
 int mytest()
 {
   char buf[20];
-
   snprintf(buf, sizeof(buf), "%s", "foo");
   return 0;
 }
-
 int main()
 {
   return (mytest());
 }
 EOF
 
-  if test "`($CC $CFLAGS -o $test $test.c) 2>&1`" = ""; then
-    echo "Checking for snprintf() in stdio.h... Yes."
+  if try $CC $CFLAGS -o $test $test.c; then
+    echo "Checking for snprintf() in stdio.h... Yes." | tee -a configure.log
 
+    echo >> configure.log
     cat >$test.c <<EOF
 #include <stdio.h>
-
 int mytest()
 {
   char buf[20];
-
   return snprintf(buf, sizeof(buf), "%s", "foo");
 }
-
 int main()
 {
   return (mytest());
 }
 EOF
 
-    if test "`($CC -c $CFLAGS $test.c) 2>&1`" = ""; then
-      echo "Checking for return value of snprintf()... Yes."
+    if try $CC -c $CFLAGS $test.c; then
+      echo "Checking for return value of snprintf()... Yes." | tee -a configure.log
     else
       CFLAGS="$CFLAGS -DHAS_snprintf_void"
       SFLAGS="$SFLAGS -DHAS_snprintf_void"
-      echo "Checking for return value of snprintf()... No."
-      echo "  WARNING: apparently snprintf() does not return a value. zlib"
-      echo "  can build but will be open to possible string-format security"
-      echo "  vulnerabilities."
+      echo "Checking for return value of snprintf()... No." | tee -a configure.log
+      echo "  WARNING: apparently snprintf() does not return a value. zlib" | tee -a configure.log
+      echo "  can build but will be open to possible string-format security" | tee -a configure.log
+      echo "  vulnerabilities." | tee -a configure.log
     fi
   else
     CFLAGS="$CFLAGS -DNO_snprintf"
     SFLAGS="$SFLAGS -DNO_snprintf"
-    echo "Checking for snprintf() in stdio.h... No."
-    echo "  WARNING: snprintf() not found, falling back to sprintf(). zlib"
-    echo "  can build but will be open to possible buffer-overflow security"
-    echo "  vulnerabilities."
+    echo "Checking for snprintf() in stdio.h... No." | tee -a configure.log
+    echo "  WARNING: snprintf() not found, falling back to sprintf(). zlib" | tee -a configure.log
+    echo "  can build but will be open to possible buffer-overflow security" | tee -a configure.log
+    echo "  vulnerabilities." | tee -a configure.log
 
+    echo >> configure.log
     cat >$test.c <<EOF
 #include <stdio.h>
-
 int mytest()
 {
   char buf[20];
-
   return sprintf(buf, "%s", "foo");
 }
-
 int main()
 {
   return (mytest());
 }
 EOF
 
-    if test "`($CC -c $CFLAGS $test.c) 2>&1`" = ""; then
-      echo "Checking for return value of sprintf()... Yes."
+    if try $CC -c $CFLAGS $test.c; then
+      echo "Checking for return value of sprintf()... Yes." | tee -a configure.log
     else
       CFLAGS="$CFLAGS -DHAS_sprintf_void"
       SFLAGS="$SFLAGS -DHAS_sprintf_void"
-      echo "Checking for return value of sprintf()... No."
-      echo "  WARNING: apparently sprintf() does not return a value. zlib"
-      echo "  can build but will be open to possible string-format security"
-      echo "  vulnerabilities."
+      echo "Checking for return value of sprintf()... No." | tee -a configure.log
+      echo "  WARNING: apparently sprintf() does not return a value. zlib" | tee -a configure.log
+      echo "  can build but will be open to possible string-format security" | tee -a configure.log
+      echo "  vulnerabilities." | tee -a configure.log
     fi
   fi
 fi
 
+# see if we can hide zlib internal symbols that are linked between separate source files
 if test "$gcc" -eq 1; then
+  echo >> configure.log
   cat > $test.c <<EOF
-#if ((__GNUC__-0) * 10 + __GNUC_MINOR__-0 >= 33)
-#  define ZLIB_INTERNAL __attribute__((visibility ("hidden")))
-#else
-#  define ZLIB_INTERNAL
-#endif
+#define ZLIB_INTERNAL __attribute__((visibility ("hidden")))
 int ZLIB_INTERNAL foo;
 int main()
 {
   return 0;
 }
 EOF
-  if test "`($CC -c $CFLAGS $test.c) 2>&1`" = ""; then
-    echo "Checking for attribute(visibility) support... Yes."
+  if tryboth $CC -c $CFLAGS $test.c; then
+    CFLAGS="$CFLAGS -DHAVE_HIDDEN"
+    SFLAGS="$SFLAGS -DHAVE_HIDDEN"
+    echo "Checking for attribute(visibility) support... Yes." | tee -a configure.log
   else
-    CFLAGS="$CFLAGS -DNO_VIZ"
-    SFLAGS="$SFLAGS -DNO_VIZ"
-    echo "Checking for attribute(visibility) support... No."
+    echo "Checking for attribute(visibility) support... No." | tee -a configure.log
   fi
 fi
 
-CPP=${CPP-"$CC -E"}
-case $CFLAGS in
-  *ASMV*)
-    if test "`$NM $test.o | grep _hello`" = ""; then
-      CPP="$CPP -DNO_UNDERLINE"
-      echo Checking for underline in external names... No.
-    else
-      echo Checking for underline in external names... Yes.
-    fi ;;
-esac
-
-rm -f $test.[co] $test $test$shared_ext
-
-# udpate Makefile
+# show the results in the log
+echo >> configure.log
+echo ALL = $ALL >> configure.log
+echo AR = $AR >> configure.log
+echo ARFLAGS = $ARFLAGS >> configure.log
+echo CC = $CC >> configure.log
+echo CFLAGS = $CFLAGS >> configure.log
+echo CPP = $CPP >> configure.log
+echo EXE = $EXE >> configure.log
+echo LDCONFIG = $LDCONFIG >> configure.log
+echo LDFLAGS = $LDFLAGS >> configure.log
+echo LDSHARED = $LDSHARED >> configure.log
+echo LDSHAREDLIBC = $LDSHAREDLIBC >> configure.log
+echo OBJC = $OBJC >> configure.log
+echo PIC_OBJC = $PIC_OBJC >> configure.log
+echo RANLIB = $RANLIB >> configure.log
+echo SFLAGS = $SFLAGS >> configure.log
+echo SHAREDLIB = $SHAREDLIB >> configure.log
+echo SHAREDLIBM = $SHAREDLIBM >> configure.log
+echo SHAREDLIBV = $SHAREDLIBV >> configure.log
+echo STATICLIB = $STATICLIB >> configure.log
+echo TEST = $TEST >> configure.log
+echo VER = $VER >> configure.log
+echo Z_U4 = $Z_U4 >> configure.log
+echo exec_prefix = $exec_prefix >> configure.log
+echo includedir = $includedir >> configure.log
+echo libdir = $libdir >> configure.log
+echo mandir = $mandir >> configure.log
+echo prefix = $prefix >> configure.log
+echo sharedlibdir = $sharedlibdir >> configure.log
+echo uname = $uname >> configure.log
+
+# udpate Makefile with the configure results
 sed < Makefile.in "
 /^CC *=/s#=.*#=$CC#
 /^CFLAGS *=/s#=.*#=$CFLAGS#
@@ -557,7 +784,8 @@ sed < Makefile.in "
 /^SHAREDLIB *=/s#=.*#=$SHAREDLIB#
 /^SHAREDLIBV *=/s#=.*#=$SHAREDLIBV#
 /^SHAREDLIBM *=/s#=.*#=$SHAREDLIBM#
-/^AR *=/s#=.*#=$AR_RC#
+/^AR *=/s#=.*#=$AR#
+/^ARFLAGS *=/s#=.*#=$ARFLAGS#
 /^RANLIB *=/s#=.*#=$RANLIB#
 /^LDCONFIG *=/s#=.*#=$LDCONFIG#
 /^LDSHAREDLIBC *=/s#=.*#=$LDSHAREDLIBC#
@@ -568,10 +796,13 @@ sed < Makefile.in "
 /^sharedlibdir *=/s#=.*#=$sharedlibdir#
 /^includedir *=/s#=.*#=$includedir#
 /^mandir *=/s#=.*#=$mandir#
+/^OBJC *=/s#=.*#= $OBJC#
+/^PIC_OBJC *=/s#=.*#= $PIC_OBJC#
 /^all: */s#:.*#: $ALL#
 /^test: */s#:.*#: $TEST#
 " > Makefile
 
+# create zlib.pc with the configure results
 sed < zlib.pc.in "
 /^CC *=/s#=.*#=$CC#
 /^CFLAGS *=/s#=.*#=$CFLAGS#
@@ -581,7 +812,8 @@ sed < zlib.pc.in "
 /^SHAREDLIB *=/s#=.*#=$SHAREDLIB#
 /^SHAREDLIBV *=/s#=.*#=$SHAREDLIBV#
 /^SHAREDLIBM *=/s#=.*#=$SHAREDLIBM#
-/^AR *=/s#=.*#=$AR_RC#
+/^AR *=/s#=.*#=$AR#
+/^ARFLAGS *=/s#=.*#=$ARFLAGS#
 /^RANLIB *=/s#=.*#=$RANLIB#
 /^EXE *=/s#=.*#=$EXE#
 /^prefix *=/s#=.*#=$prefix#
@@ -594,3 +826,6 @@ sed < zlib.pc.in "
 " | sed -e "
 s/\@VERSION\@/$VER/g;
 " > zlib.pc
+
+# done
+leave 0