Macro definitions for headers, where to put them?

When defining macros that headers rely on, such as _FILE_OFFSET_BITS, FUSE_USE_VERSION, _GNU_SOURCE among others, where is the best place to put them?

Some possibilities I've considered include

1. At the top of the any source files that rely on definitions exposed by headers included in that file
2. Immediately before the include for the relevant header(s)
3. Define at the CPPFLAGS level via the compiler? (such as -D_FILE_OFFSET_BITS=64) for the:
   1. Entire source repo
   2. The whole project
   3. Just the sources that require it
4. In project headers, which should also include those relevant headers to which the macros apply
5. Some other place I haven't thought of, but is infinitely superior

A note: Justification by applicability to make, autotools, and other build systems is a factor in my decision.