Document status

Preliminary support of this spec was implemented in dpkg 1.17.2. A patch for sbuild exists: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=731798

Problem description

For some compilation scenarios it is required to build-depend on a different set of binary packages than specified in the Build-Depends line. The two most important scenarios are:

This specification describes two possible extensions of the Build-Depends field syntax. These extensions allow the marking of build dependencies as being needed or not needed when a specific build profile is activated. It also defines a new field called "Build-Profiles" which aids in marking binary packages as being built or not built whilst a certain build profile is activated or having been built with a certain set of build profiles activated.

Build profiles can be activated by setting the environment variable DEB_BUILD_PROFILES or by using the -P option with dpkg-buildpackage (or -o Apt::Build-Profiles for apt, or --profiles in sbuild). More than one build profile can be activated at a time. Multiple profiles are specified by separating them with commas in commandline arguments and by separating them with spaces in the DEB_BUILD_PROFILES environment variable. The initial profile names are "stage1", "stage2", "notest" and "cross". Other possibilities are "nodoc" or "embedded".

Binary packages which were built with one or more build profiles activated will have these profiles appended to their version number.

Build-Depends syntax extension

An example demonstrating the build profile syntax:

Build-Depends: foo (>= 1.0) [i386 arm] <!profile.stage1 !profile.cross>, bar

This specification introduces a new pair of brackets (using < as the opening and > as the closing bracket) to be used after the architecture qualification list. Just as in the architecture qualification list, the literals within the <> brackets form a disjunction.

Every literal in a disjunction follows the following regular expression:

([a-z][a-z0-9-]*)\.([a-z][a-z0-9-]*)

The first group is called a namespace and the namespace "profile" is used to support build profiles. The second group is called a label and specifies the profile name.

These literals can be negated by using an exclamation mark as a prefix. Just as in architecture qualifications, either all literals must be positive or all must be negative.

No other namespaces besides "profile" exist yet but it is forbidden to mix different namespaces within one disjunction.

Future extensions

The Build-Profiles field

In debian/control binary package stanzas, the content of the Build-Profiles field specifies the list of build profiles for which that binary package does or does not build. This list can either be all positive or all negative. Entries are negated by using an exclamation mark as a prefix.

Build-Profiles: !cross !stage1

If a binary package stanza in a debian/control file does not contain a Build-Profiles field, then it implicitly means that it builds with all build profiles.

In .dsc file and Sources files, the Build-Profiles field is automatically generated and specifies a list of build profiles which that source package supports. It is therefore the union of the build profile names given in the Build-Depends field in the debian/control file and the build profile names given in the Build-Profiles field in the binary package stanzas in the debian/control file.

The Built-For-Profiles field

In *.changes and Packages files, the content of the Built-For-Profiles field specifies the list of build profiles for which that binary or source package was built for. It is also possible to identify binary packages which were built with one or more build profiles activated through their version number.

The DEB_BUILD_PROFILES environment variable

The DEB_BUILD_PROFILES environment variable contains a space separated list of activated profiles. The content of this variable must be honored by all tools involved in package compilation. Here an example for debian/rules:

ifeq ($(firstword $(filter stage1,$(DEB_BUILD_PROFILES))),stage1)
    DH_OPTIONS += -Nlibdb5.1-sql
    CONFIGURE_SWITCHES += --disable-sql
else
    CONFIGURE_SWITCHES += --enable-sql
endif

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