g++ 4.3 more strict with declarations

I've been moving a bunch of old C++ code over to g++ 4.3 and have found that gcc is now more strict on declarations and I often receive these sorts of errors:

error: ‘memset’ was not declared in this scope
error: ‘strncmp’ was not declared in this scope

I'm going to continually update this look-up table, which will explain what to do when receiving any of these errors:

Error	Resolution
error: ‘memset’ was not declared in this scope	Add #include <cstring>
error: ‘strncmp’ was not declared in this scope