+
+ <sect id="built-using">
+ <heading>Additional source packages used to build the binary
+ - <tt>Built-Using</tt>
+ </heading>
+
+ <p>
+ Some binary packages incorporate parts of other packages when built
+ but do not have to depend on those packages. Examples include
+ linking with static libraries or incorporating source code from
+ another package during the build. In this case, the source packages
+ of those other packages are a required part of the complete source
+ (the binary package is not reproducible without them).
+ </p>
+
+ <p>
+ A <tt>Built-Using</tt> field must list the corresponding source
+ package for any such binary package incorporated during the build
+ <footnote>
+ <tt>Build-Depends</tt> in the source package is not adequate since
+ it (rightfully) does not document the exact version used in the
+ build.
+ </footnote>,
+ including an "exactly equal" ("=") version relation on the version
+ that was used to build that binary package<footnote>
+ The archive software might reject packages that refer to
+ non-existent sources.
+ </footnote>.
+ </p>
+
+ <p>
+ A package using the source code from the gcc-4.6-source
+ binary package built from the gcc-4.6 source package would
+ have this field in its control file:
+ <example compact="compact">
+Built-Using: gcc-4.6 (= 4.6.0-11)
+ </example>
+ </p>
+
+ <p>
+ A package including binaries from grub2 and loadlin would
+ have this field in its control file:
+ <example compact="compact">
+Built-Using: grub2 (= 1.99-9), loadlin (= 1.6e-1)
+ </example>
+ </p>
+ </sect>