The default version of GCC that ships on Raspian has an issue. The file '/usr/lib/arm-linux-gnueabihf/libarmmem-v7l.so' has a faulty implementation of 'memcpy()' and possibly 'memset()'. Changing to the newer versions doens't work, as they're just symlinks to v7.

To resolve this, download and build this shared object:

https://github.com/simonjhall/copies-and-fills

Then, set the linker's preload value to point to that '.so' file (You may need to edit '/etc/ld.so.preload')