HTTP/2: fixed null pointer dereference with server push. r->headers_in.host can be NULL in ngx_http_v2_push_resource(). This happens when a request is terminated with 400 before the :authority or Host header is parsed, and either pushing is enabled on the server{} level or error_page 400 redirects to a location with pushes configured. Found by Coverity (CID 1429156).

# Copyright (C) Nginx, Inc.


if [ $USE_THREADS = YES ]; then

    if [ "$NGX_PLATFORM" = win32 ]; then
        cat << END

$0: --with-threads is not supported on Windows

END
        exit 1
    fi

    have=NGX_THREADS . auto/have
    CORE_DEPS="$CORE_DEPS $THREAD_POOL_DEPS"
    CORE_SRCS="$CORE_SRCS $THREAD_POOL_SRCS"
    CORE_LIBS="$CORE_LIBS -lpthread"
fi