Applying ./patches/010-no-cxx.patch using plaintext: 
patching file Makefile.am
patching file configure.ac
autoreconf: export WARNINGS=
autoreconf: Entering directory '.'
autoreconf: configure.ac: not using Gettext
autoreconf: running: /builder/shared-workdir/build/sdk/staging_dir/host/bin/aclocal -I /builder/shared-workdir/build/sdk/staging_dir/target-arm_xscale_musl_eabi/host/share/aclocal -I /builder/shared-workdir/build/sdk/staging_dir/hostpkg/share/aclocal -I /builder/shared-workdir/build/sdk/staging_dir/target-arm_xscale_musl_eabi/usr/share/aclocal -I m4 -I . --force 
autoreconf: configure.ac: tracing
autoreconf: configure.ac: not using Libtool
autoreconf: configure.ac: not using Intltool
autoreconf: configure.ac: not using Gtkdoc
autoreconf: running: /builder/shared-workdir/build/sdk/staging_dir/host/bin/autoconf --include=/builder/shared-workdir/build/sdk/staging_dir/target-arm_xscale_musl_eabi/host/share/aclocal --include=/builder/shared-workdir/build/sdk/staging_dir/hostpkg/share/aclocal --include=/builder/shared-workdir/build/sdk/staging_dir/target-arm_xscale_musl_eabi/usr/share/aclocal --include=m4 --include=. --prepend-include=/builder/shared-workdir/build/sdk/staging_dir/host/share/aclocal --force
configure.ac:397: warning: The macro `AC_HEADER_STDC' is obsolete.
configure.ac:397: You should run autoupdate.
./lib/autoconf/headers.m4:704: AC_HEADER_STDC is expanded from...
configure.ac:397: the top level
autoreconf: running: /builder/shared-workdir/build/sdk/staging_dir/host/bin/autoheader --include=/builder/shared-workdir/build/sdk/staging_dir/target-arm_xscale_musl_eabi/host/share/aclocal --include=/builder/shared-workdir/build/sdk/staging_dir/hostpkg/share/aclocal --include=/builder/shared-workdir/build/sdk/staging_dir/target-arm_xscale_musl_eabi/usr/share/aclocal --include=m4 --include=. --prepend-include=/builder/shared-workdir/build/sdk/staging_dir/host/share/aclocal --force
autoreconf: running: /builder/shared-workdir/build/sdk/staging_dir/host/bin/automake --add-missing --force-missing
configure.ac:25: installing './compile'
configure.ac:6: installing './install-sh'
configure.ac:6: installing './missing'
Makefile.am: installing './depcomp'
autoreconf: Leaving directory '.'
configure: WARNING: unrecognized options: --disable-nls
configure: loading site script /builder/shared-workdir/build/sdk/include/site/arm
checking for a BSD-compatible install... /builder/shared-workdir/build/sdk/staging_dir/host/bin/install -c
checking whether build environment is sane... yes
checking for arm-openwrt-linux-strip... arm-openwrt-linux-muslgnueabi-strip
checking for a race-free mkdir -p... /bin/mkdir -p
checking for gawk... gawk
checking whether make sets $(MAKE)... yes
checking whether make supports nested variables... yes
checking for arm-openwrt-linux-ranlib... arm-openwrt-linux-muslgnueabi-gcc-ranlib
checking for arm-openwrt-linux-gcc... arm-openwrt-linux-muslgnueabi-gcc
checking whether the C compiler works... yes
checking for C compiler default output file name... a.out
checking for suffix of executables... 
checking whether we are cross compiling... yes
checking for suffix of object files... o
checking whether the compiler supports GNU C... yes
checking whether arm-openwrt-linux-muslgnueabi-gcc accepts -g... yes
checking for arm-openwrt-linux-muslgnueabi-gcc option to enable C11 features... none needed
checking whether arm-openwrt-linux-muslgnueabi-gcc understands -c and -o together... yes
checking whether make supports the include directive... yes (GNU style)
checking dependency style of arm-openwrt-linux-muslgnueabi-gcc... none
checking pkg-config is at least version 0.9.0... yes
checking for clock_gettime in -lrt... yes
checking for pthread_create in -lpthread... yes
checking for exp in -lm... yes
checking for popt... yes
checking for libconfig... yes
checking for libdaemon... yes
checking for libssl,libcrypto... no
configure: error: Package requirements (libssl,libcrypto) were not met:

Package 'libssl', required by 'virtual:world', not found
Package 'libcrypto', required by 'virtual:world', not found

Consider adjusting the PKG_CONFIG_PATH environment variable if you
installed software in a non-standard prefix.

Alternatively, you may set the environment variables SSL_CFLAGS
and SSL_LIBS to avoid the need to call pkg-config.
See the pkg-config man page for more details.
make[3]: *** [Makefile:125: /builder/shared-workdir/build/sdk/build_dir/target-arm_xscale_musl_eabi/shairport-sync-openssl/shairport-sync-3.3.9/.configured_68b329da9893e34099c7d8ad5cb9c940] Error 1
time: package/feeds/packages/shairport-sync/openssl/compile#5.20#0.83#8.62