Core: fixed environment on exit. On exit environment allocated from a pool is no longer available, leading to a segmentation fault if, for example, a library tries to use it from an atexit() handler. Fix is to allocate environment via ngx_alloc() instead, and explicitly free it using a pool cleanup handler if it's no longer used (e.g., on configuration reload).

# 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