The shared library system for linux, especially when it comes to libc, is (choose one): archaic|complex|awesome. Today in trying to run some software on our local cluster, I encountered this lovely error:
/lib/x86_64-linux-gnu/libc.so.6: version `GLIBC_2.14' not found
Why was this occurring? For some reason, there was a version bump in the glibc for the memcpy instruction. How memcpy’s interface could possibly changed in a non-backward-compatible fashion, I don’t know. Still, since my local machine has a later libc then our cluster machines, I’m effectively boned.
There is a way around this, namely, I can ask the compiler to emit references to a specific, older version:__asm__(".symver memcpy,[email protected]_2.2.5");
Unfortunately, this code has to appear before any other uses of memcpy! Rather then update a whole lot of code, I took advantage of the -include option for gcc. I simply created a file with my desired symbol override:# gcc-preinclude.h __asm__(".symver memcpy,[email protected]_2.2.5");
and forced the build (here, autotools) to always include that before any other code:./configure CC=gcc -include /path/to/gcc-preinclude.h ...
And away we go. A full rebuild and I’m back to a usable program again. Hurray!