Compiled on RPI4B-4G with 5.10.77-piCore-v8

Compile Flags:
CPPFLAGS='-DNDEBUG'
CFLAGS='-march=armv8-a+crc -mtune=cortex-a72 -Os -pipe -flto -fuse-linker-plugin -fno-exceptions'
CXXFLAGS='-march=armv8-a+crc -mtune=cortex-a72 -Os -pipe -flto -fuse-linker-plugin -fno-exceptions -fno-rtti'
LDFLAGS='-Wl,-O1'
export CPPFLAGS CFLAGS CXXFLAGS LDFLAGS

Dependencies:
compiletc
libxml2-dev
llvm-bin

Commands:

# fix lto
P=/usr/local/libexec/gcc/aarch64-unknown-linux-gnu/10.2.0/liblto_plugin.so.0.0.0
sudo mkdir -p /usr/local/lib/bfd-plugins
sudo ln -sfv $P /usr/local/lib/bfd-plugins/liblto_plugin.so

wget https://github.com/nghttp2/nghttp2/releases/download/v1.47.0/nghttp2-1.47.0.tar.gz

tar -xf nghttp2-1.47.0.tar.gz

cd nghttp2-1.47.0/

./configure --prefix=/usr/local --localstatedir=/var --enable-lib-only

time make -j4
real    0m 11.34s
user    0m 20.56s
sys     0m 3.92s

DESTDIR=/tmp/packing-nghttp2 make install

llvm-strip --strip-debug /tmp/packing-nghttp2/usr/local/lib/libnghttp2.a
strip --strip-unneeded /tmp/packing-nghttp2/usr/local/lib/libnghttp2.so.14.21.2

# dev
mkdir -p /tmp/packing-nghttp2-dev/usr/local/lib
mv /tmp/packing-nghttp2/usr/local/lib/pkgconfig /tmp/packing-nghttp2-dev/usr/local/lib
mv /tmp/packing-nghttp2/usr/local/lib/*a /tmp/packing-nghttp2-dev/usr/local/lib
mv /tmp/packing-nghttp2/usr/local/include /tmp/packing-nghttp2-dev/usr/local/

cd /tmp/packing-nghttp2
rm -fr ./usr/local/bin ./usr/local/share/man ./usr/local/share/doc
======================================================================================================================

    Package version: 1.47.0
    Library version: 35:2:21
    Install prefix:  /usr/local
    System types:
      Build:         aarch64-unknown-linux-gnu
      Host:          aarch64-unknown-linux-gnu
      Target:        aarch64-unknown-linux-gnu
    Compiler:
      C compiler:     gcc
      CFLAGS:         -march=armv8-a+crc -mtune=cortex-a72 -Os -pipe -flto -fuse-linker-plugin -fno-exceptions
      LDFLAGS:        -Wl,-O1
      C++ compiler:   g++ -std=c++14
      CXXFLAGS:       -march=armv8-a+crc -mtune=cortex-a72 -Os -pipe -flto -fuse-linker-plugin -fno-exceptions -fno-rtti
      CXXCPP:         g++ -E -std=c++14
      C preprocessor: gcc -E
      CPPFLAGS:       -DNDEBUG
      WARNCFLAGS:
      WARNCXXFLAGS:
      CXX1XCXXFLAGS:
      EXTRACFLAG:     -fvisibility=hidden
      BPFCFLAGS:
      EXTRABPFCFLAGS:
      LIBS:
      DEFS:           -DHAVE_CONFIG_H
      EXTRA_DEFS:
    Library:
      Shared:         yes
      Static:         yes
    Libtool:
      LIBTOOL_LDFLAGS:
    Python:
      Python:         :
      PYTHON_VERSION:
      pyexecdir:
      PYTHON_CPPFLAGS:
      PYTHON_LIBS:
      Cython:
    Test:
      CUnit:          no (CFLAGS='' LIBS='')
      Failmalloc:     yes
    Libs:
      OpenSSL:        no (CFLAGS='' LIBS='')
      Libxml2:        yes (CFLAGS='-I/usr/local/include/libxml2' LIBS='-L/usr/local/lib -lxml2')
      Libev:          no (CFLAGS='' LIBS='')
      Libc-ares:      no (CFLAGS='' LIBS='')
      libngtcp2:      no (CFLAGS='' LIBS='')
      libngtcp2_crypto_openssl: no (CFLAGS='' LIBS='')
      libngtcp2_crypto_boringssl: no (CFLAGS='' LIBS='')
      libnghttp3:     no (CFLAGS='' LIBS='')
      libbpf:         no (CFLAGS='' LIBS='')
      Libevent(SSL):  no (CFLAGS='' LIBS='')
      Jansson:        no (CFLAGS='' LIBS='')
      Jemalloc:       no (CFLAGS='' LIBS='')
      Zlib:           yes (CFLAGS='' LIBS='-lz')
      Systemd:        no (CFLAGS='' LIBS='')
      Boost CPPFLAGS:
      Boost LDFLAGS:
      Boost::ASIO:
      Boost::System:
      Boost::Thread:
    Third-party:
      http-parser:    no
      MRuby:          no (CFLAGS='' LIBS='')
      Neverbleed:     no
    Features:
      Applications:   no
      HPACK tools:    no
      Libnghttp2_asio:no
      Examples:       no
      Python bindings:no
      Threading:      yes
      HTTP/3 (EXPERIMENTAL): no