## page was renamed from ReproducibleBuilds/TimestampFromCPPMacros

`__DATE__`, `__TIME__` and `__TIMESTAMP` are part of the [[https://gcc.gnu.org/onlinedocs/cpp/Standard-Predefined-Macros.html|standard predefined macros of the C pre-processor]].

Now that GCC has [[https://gcc.gnu.org/git/?p=gcc.git;a=commitdiff;h=e3e8c48c4a494d9da741c1c8ea6c4c0b7c4ff934|accepted]] our patch to support [[../TimestampsProposal|SOURCE_DATE_EPOCH]], `__DATE__` and `__TIME__` will instead use that deterministic value, and package maintainers shouldn't need to do anything extra to make their builds reproducible.

We missed out `__TIMESTAMP__` by mistake, but we will probably send in another patch to GCC to fix that.

[[https://tests.reproducible-builds.org/debian/issues/unstable/timestamps_from_cpp_macros_issue.html|Known affected packages]] - this should soon drop in number as we rebuild things with the newer GCC. However there are [[https://codesearch.debian.net/search?q=__TIMESTAMP__&literal=1|still some packages]] using `__TIMESTAMP__`.