title: how do I remove `GLIBC_2.27' requirement at compile time?
body: <p>I've been using a docker image for c++ compilation. It's based on Ubuntu 18.04. When I attempt to run on some Ubuntu 16 systems, I get this message:</p>
  
  <p>/lib/x86_64-linux-gnu/libm.so.6: version `GLIBC_2.27' not found</p>
  
  <p>I'll post the full ldd output below. I like using the newer compiler. I would prefer to not compile with an older Linux base image (but I will if necessary). I statically link most libraries, but I haven't been statically linking glibc. A number of web sources recommend against that. Is there some way I can tell my newer compiler (gcc 7.3) to not require the newer glibc? ldd -v output:</p>
  
  <pre><code>    linux-vdso.so.1 (0x00007ffd167cf000)
      libpthread.so.0 =&gt; /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007eff77399000)
      librt.so.1 =&gt; /lib/x86_64-linux-gnu/librt.so.1 (0x00007eff77191000)
      libm.so.6 =&gt; /lib/x86_64-linux-gnu/libm.so.6 (0x00007eff76df3000)
      libgcc_s.so.1 =&gt; /lib/x86_64-linux-gnu/libgcc_s.so.1 (0x00007eff76bdb000)
      libc.so.6 =&gt; /lib/x86_64-linux-gnu/libc.so.6 (0x00007eff767ea000)
      /lib64/ld-linux-x86-64.so.2 (0x00007eff79f90000)
  
      Version information:
      lbrycrd-linux (4)/lbrycrdd:
          ld-linux-x86-64.so.2 (GLIBC_2.3) =&gt; /lib64/ld-linux-x86-64.so.2
          librt.so.1 (GLIBC_2.2.5) =&gt; /lib/x86_64-linux-gnu/librt.so.1
          libm.so.6 (GLIBC_2.27) =&gt; /lib/x86_64-linux-gnu/libm.so.6
          libm.so.6 (GLIBC_2.2.5) =&gt; /lib/x86_64-linux-gnu/libm.so.6
          libgcc_s.so.1 (GCC_3.3) =&gt; /lib/x86_64-linux-gnu/libgcc_s.so.1
          libgcc_s.so.1 (GCC_3.0) =&gt; /lib/x86_64-linux-gnu/libgcc_s.so.1
          libgcc_s.so.1 (GCC_4.2.0) =&gt; /lib/x86_64-linux-gnu/libgcc_s.so.1
          libpthread.so.0 (GLIBC_2.3.4) =&gt; /lib/x86_64-linux-gnu/libpthread.so.0
          libpthread.so.0 (GLIBC_2.3.3) =&gt; /lib/x86_64-linux-gnu/libpthread.so.0
          libpthread.so.0 (GLIBC_2.2.5) =&gt; /lib/x86_64-linux-gnu/libpthread.so.0
          libpthread.so.0 (GLIBC_2.3.2) =&gt; /lib/x86_64-linux-gnu/libpthread.so.0
          libc.so.6 (GLIBC_2.15) =&gt; /lib/x86_64-linux-gnu/libc.so.6
          libc.so.6 (GLIBC_2.4) =&gt; /lib/x86_64-linux-gnu/libc.so.6
          libc.so.6 (GLIBC_2.14) =&gt; /lib/x86_64-linux-gnu/libc.so.6
          libc.so.6 (GLIBC_2.8) =&gt; /lib/x86_64-linux-gnu/libc.so.6
          libc.so.6 (GLIBC_2.7) =&gt; /lib/x86_64-linux-gnu/libc.so.6
          libc.so.6 (GLIBC_2.9) =&gt; /lib/x86_64-linux-gnu/libc.so.6
          libc.so.6 (GLIBC_2.10) =&gt; /lib/x86_64-linux-gnu/libc.so.6
          libc.so.6 (GLIBC_2.3.2) =&gt; /lib/x86_64-linux-gnu/libc.so.6
          libc.so.6 (GLIBC_2.3) =&gt; /lib/x86_64-linux-gnu/libc.so.6
          libc.so.6 (GLIBC_2.2.5) =&gt; /lib/x86_64-linux-gnu/libc.so.6
          libc.so.6 (GLIBC_2.3.4) =&gt; /lib/x86_64-linux-gnu/libc.so.6
      /lib/x86_64-linux-gnu/libpthread.so.0:
          ld-linux-x86-64.so.2 (GLIBC_2.2.5) =&gt; /lib64/ld-linux-x86-64.so.2
          ld-linux-x86-64.so.2 (GLIBC_PRIVATE) =&gt; /lib64/ld-linux-x86-64.so.2
          libc.so.6 (GLIBC_2.14) =&gt; /lib/x86_64-linux-gnu/libc.so.6
          libc.so.6 (GLIBC_2.3.2) =&gt; /lib/x86_64-linux-gnu/libc.so.6
          libc.so.6 (GLIBC_2.4) =&gt; /lib/x86_64-linux-gnu/libc.so.6
          libc.so.6 (GLIBC_2.2.5) =&gt; /lib/x86_64-linux-gnu/libc.so.6
          libc.so.6 (GLIBC_PRIVATE) =&gt; /lib/x86_64-linux-gnu/libc.so.6
      /lib/x86_64-linux-gnu/librt.so.1:
          libpthread.so.0 (GLIBC_2.3.2) =&gt; /lib/x86_64-linux-gnu/libpthread.so.0
          libpthread.so.0 (GLIBC_PRIVATE) =&gt; /lib/x86_64-linux-gnu/libpthread.so.0
          libpthread.so.0 (GLIBC_2.2.5) =&gt; /lib/x86_64-linux-gnu/libpthread.so.0
          libc.so.6 (GLIBC_2.14) =&gt; /lib/x86_64-linux-gnu/libc.so.6
          libc.so.6 (GLIBC_2.3.2) =&gt; /lib/x86_64-linux-gnu/libc.so.6
          libc.so.6 (GLIBC_2.4) =&gt; /lib/x86_64-linux-gnu/libc.so.6
          libc.so.6 (GLIBC_2.2.5) =&gt; /lib/x86_64-linux-gnu/libc.so.6
          libc.so.6 (GLIBC_PRIVATE) =&gt; /lib/x86_64-linux-gnu/libc.so.6
      /lib/x86_64-linux-gnu/libm.so.6:
          ld-linux-x86-64.so.2 (GLIBC_PRIVATE) =&gt; /lib64/ld-linux-x86-64.so.2
          libc.so.6 (GLIBC_2.4) =&gt; /lib/x86_64-linux-gnu/libc.so.6
          libc.so.6 (GLIBC_2.2.5) =&gt; /lib/x86_64-linux-gnu/libc.so.6
          libc.so.6 (GLIBC_PRIVATE) =&gt; /lib/x86_64-linux-gnu/libc.so.6
      /lib/x86_64-linux-gnu/libgcc_s.so.1:
          libc.so.6 (GLIBC_2.14) =&gt; /lib/x86_64-linux-gnu/libc.so.6
          libc.so.6 (GLIBC_2.2.5) =&gt; /lib/x86_64-linux-gnu/libc.so.6
      /lib/x86_64-linux-gnu/libc.so.6:
          ld-linux-x86-64.so.2 (GLIBC_2.3) =&gt; /lib64/ld-linux-x86-64.so.2
          ld-linux-x86-64.so.2 (GLIBC_PRIVATE) =&gt; /lib64/ld-linux-x86-64.so.2
  </code></pre>