Debian 的包发布机制都是怎样的？每次发布新版本都要把依赖也改到最新的版本？

比如我当前的版本 network-manager 处理 clone mac 地址有 BUG，我想更新到 testing 试试

$ sudo apt install  --no-install-recommends network-manager/testing
Reading package lists... Done                                                 
Building dependency tree                                                    
Reading state information... Done                                       
Selected version '1.10.6-3' (Debian:testing [amd64]) for 'network-manager'      
Selected version '2.27-3' (Debian:testing [amd64]) for 'libc6' because of 'network-manager'
Selected version '0.52.20-4' (Debian:testing [amd64]) for 'libnewt0.52' because of 'network-manager'
Selected version '1.10.6-3' (Debian:testing [amd64]) for 'libnm0' because of 'network-manager'
Some packages could not be installed. This may mean that you have

我的理解是，如果只是调用 libc6 的 so，不使用新特性的话，用老版本的 so 也是可以兼容的，为什么就一定要依赖到最新的 libc6 呢？

尝试升级 libc6 到 teseting，看到 The following packages were automatically installed and are no longer required 还有 The following packages will be REMOVED:，又是懵逼。

我只不过是想单独更新一个包而已啊。

$ sudo apt install libc6/testing libc6-dev/testing
Reading package lists... Done
Building dependency tree       
Reading state information... Done
Selected version '2.27-3' (Debian:testing [amd64]) for 'libc6'
Selected version '2.27-3' (Debian:testing [amd64]) for 'libc6-dev'
Selected version '2.27-3' (Debian:testing [amd64]) for 'libc-dev-bin' because of 'libc6-dev'
The following packages were automatically installed and are no longer required:
  bc cups-browsed cups-core-drivers cups-daemon cups-filters cups-filters-core-drivers cups-ppdc cups-server-common dc foomatic-db-compressed-ppds
  foomatic-db-engine hp-ppd hplip-data libclang1-5.0 libcupscgi1 libcupsmime1 libcupsppdc1 libfontembed1 libgutenprint2 libhpmud0 liblouisutdml-bin
  liblouisutdml-data liblouisutdml7 libomp-dev libomp5 libqpdf17 libsane-hpaio libsnmp-base libsnmp30 llvm-5.0 llvm-5.0-dev llvm-5.0-runtime mscompress
  openprinting-ppds printer-driver-all printer-driver-brlaser printer-driver-c2050 printer-driver-c2esp printer-driver-cjet printer-driver-dymo
  printer-driver-escpr printer-driver-foo2zjs printer-driver-foo2zjs-common printer-driver-fujixerox printer-driver-hpijs printer-driver-m2300w
  printer-driver-min12xxw printer-driver-pnm2ppa printer-driver-ptouch printer-driver-pxljr printer-driver-sag-gdi python3-pexpect python3-ptyprocess
  python3-renderpm python3-reportlab python3-reportlab-accel qpdf ssl-cert
Use 'sudo apt autoremove' to remove them.
The following additional packages will be installed:
  libc-dev-bin
Suggested packages:
  glibc-doc locales
The following packages will be REMOVED:
  clang-5.0 cups hplip lib32gcc1 lib32stdc++6 libc-bin libc6-dbg libc6-i386 libc6-x32 libclang-common-5.0-dev libx32gcc1 locales printer-driver-gutenprint
  printer-driver-hpcups printer-driver-postscript-hp printer-driver-splix task-english task-print-server
The following packages will be upgraded:
  libc-dev-bin libc6 libc6-dev
WARNING: The following essential packages will be removed.
This should NOT be done unless you know exactly what you are doing!
  libc-bin
3 upgraded, 0 newly installed, 18 to remove and 0 not upgraded.
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