Simple work-around for running the 64-bit Adobe Flash plug-in version 10 on Athlon64 processors without support for the lahf instruction. Compile with: cc -fPIC -shared -nostdlib -lc -oflashplugin-lahf-fix.so flashplugin-lahf-fix.c Then place the .so file in the plug-in directory (e.g. $HOME/.mozilla/plugins) or use LD_PRELOAD to force Firefox to load the library.