GCC has an option preventing casting from unsigned to signed

[tiffany352]

The -pedantic option will prevent many such weak casts.

[mcinglis]

Can you elaborate? I know that -Wsign-conversion enables warnings about implicit conversions that will change signs, but it tends to be more of a pain than necessary, and seems to encourage unsigned variables to spread (e.g. use size_t for any parameter to a calloc).