Bug#18818 configure: No longer finds OpenSSL on Mac OS X

- Eval shrext_cmds variable before using it


acinclude.m4:
  eval the shrext_cmds variable before using it. This is the same fix as in ltmain.sh which has a comment describing how this works on Darwin.
  The bug describes it as not working for openSSL but as the same syntax and variable is used for zlib it has to be fixed there as well.

acinclude.m4

@@ -311,8 +311,9 @@ case $SYSTEM_TYPE in
         ;;
       *)
         # Just to be safe, we test for ".so" anyway
+	eval shrexts=\"$shrext_cmds\"
         if test \( -f "$mysql_zlib_dir/lib/libz.a"  -o -f "$mysql_zlib_dir/lib/libz.so" -o \
-                   -f "$mysql_zlib_dir/lib/libz$shrext_cmds" \) \
+                   -f "$mysql_zlib_dir/lib/libz$shrexts" \) \
                 -a -f "$mysql_zlib_dir/include/zlib.h"; then
           ZLIB_INCLUDES="-I$mysql_zlib_dir/include"
           ZLIB_LIBS="-L$mysql_zlib_dir/lib -lz"
@@ -967,6 +968,7 @@ AC_DEFUN([MYSQL_CHECK_VIO], [
 AC_DEFUN([MYSQL_FIND_OPENSSL], [
   incs="$1"
   libs="$2"
+  eval shrexts=\"$shrext_cmds\"
   case "$incs---$libs" in
     ---)
       for d in /usr/ssl/include /usr/local/ssl/include /usr/include \
@@ -981,7 +983,7 @@ AC_DEFUN([MYSQL_FIND_OPENSSL], [
 /usr/lib /usr/lib64 /opt/ssl/lib /opt/openssl/lib \
 /usr/freeware/lib32 /usr/local/lib/ ; do
       # Just to be safe, we test for ".so" anyway
-      if test -f $d/libssl.a || test -f $d/libssl.so || test -f $d/libssl$shrext_cmds ; then
+      if test -f $d/libssl.a || test -f $d/libssl.so || test -f $d/libssl$shrexts ; then
         OPENSSL_LIB=$d
       fi
       done
@@ -994,7 +996,7 @@ AC_DEFUN([MYSQL_FIND_OPENSSL], [
         OPENSSL_INCLUDE=-I$incs
       fi
       # Just to be safe, we test for ".so" anyway
-      if test -f $libs/libssl.a || test -f $libs/libssl.so || test -f $libs/libssl$shrext_cmds ; then
+      if test -f $libs/libssl.a || test -f $libs/libssl.so || test -f "$libs/libssl$shrexts" ; then
         OPENSSL_LIB=$libs
       fi
       ;;