*Don't* configure zlib so we get the generic zconf.h

code/zlib-1.3.1/zconf.h

@@ -433,11 +433,11 @@ typedef uLong FAR uLongf;
    typedef unsigned long z_crc_t;
 #endif
 
-#if 1    /* was set to #if 1 by ./configure */
+#ifdef HAVE_UNISTD_H    /* may be set to #if 1 by ./configure */
 #  define Z_HAVE_UNISTD_H
 #endif
 
-#if 1    /* was set to #if 1 by ./configure */
+#ifdef HAVE_STDARG_H    /* may be set to #if 1 by ./configure */
 #  define Z_HAVE_STDARG_H
 #endif
 

misc/update-libs.sh

@@ -44,7 +44,7 @@ prepare "https://downloads.xiph.org/releases/ogg/libogg-${OGG_VERSION}.tar.gz" "
 prepare "https://downloads.xiph.org/releases/vorbis/libvorbis-${VORBIS_VERSION}.tar.gz" "./configure" "\./\(include\|lib\)/.*\.[ch]"
 prepare "https://downloads.xiph.org/releases/opus/opus-${OPUS_VERSION}.tar.gz" "./configure" "\./\(celt\|include\|silk\|src\)/.*\.[ch]"
 prepare "https://downloads.xiph.org/releases/opus/opusfile-${OPUSFILE_VERSION}.tar.gz" "./configure" "\./\(include\|src\)/.*\.[ch]"
-prepare "https://zlib.net/zlib-${ZLIB_VERSION}.tar.gz" "./configure" "\./[^/]*\.[ch]" "\./gz.*\.[c]"
+prepare "https://zlib.net/zlib-${ZLIB_VERSION}.tar.gz" "" "\./[^/]*\.[ch]" "\./gz.*\.[c]"
 prepare "https://www.ijg.org/files/jpegsrc.v${JPEG_VERSION}.tar.gz" "./configure" "\./\(j.*\.c\|.*\.h\)" "\./\(jmem\(ansi\|dos\|mac\|name\)\|jpegtran\)\.c"
 prepare "https://curl.se/download/curl-${CURL_VERSION}.tar.gz" "./configure --with-openssl" "\.*/include/.*\.h"
 prepare "https://github.com/kcat/openal-soft/archive/refs/tags/${OPENAL_VERSION}.tar.gz" "" "\./include/AL/.*\.h"