or system information; the GNU style variables should be
used for that.
</p>
+
+ <sect1 id="debianrules-options">
+ <heading><file>debian/rules</file> and
+ <tt>DEB_BUILD_OPTIONS</tt></heading>
+
+ <p>
+ Supporting the standardized environment variable
+ <tt>DEB_BUILD_OPTIONS</tt> is recommended. This variable can
+ contain several flags to change how a package is compiled and
+ built. Each flag must be in the form <var>flag</var> or
+ <var>flag</var>=<var>options</var>. If multiple flags are
+ given, they must be separated by whitespace.<footnote>
+ Some packages support any delimiter, but whitespace is the
+ easiest to parse inside a makefile and avoids ambiguity with
+ flag values that contain commas.
+ </footnote>
+ <var>flag</var> must start with a lowercase letter
+ (<tt>a-z</tt>) and consist only of lowercase letters,
+ numbers (<tt>0-9</tt>), and the characters
+ <tt>-</tt> and <tt>_</tt> (hyphen and underscore).
+ <var>options</var> must not contain whitespace. The same
+ tag should not be given multiple times with conflicting
+ values. Package maintainers may assume that
+ <tt>DEB_BUILD_OPTIONS</tt> will not contain conflicting tags.
+ </p>
+
+ <p>
+ The meaning of the following tags has been standardized:
+ <taglist>
+ <tag>noopt</tag>
+ <item>
+ The presence of this tag means that the package should
+ be compiled with a minimum of optimization. For C
+ programs, it is best to add <tt>-O0</tt> to
+ <tt>CFLAGS</tt> (although this is usually the default).
+ Some programs might fail to build or run at this level
+ of optimization; it may be necessary to use
+ <tt>-O1</tt>, for example.
+ </item>
+ <tag>nostrip</tag>
+ <item>
+ This tag means that the debugging symbols should not be
+ stripped from the binary during installation, so that
+ debugging information may be included in the package.
+ </item>
+ <tag>parallel=n</tag>
+ <item>
+ This tag means that the package should be built using up
+ to <tt>n</tt> parallel processes if the package build
+ system supports this.<footnote>
+ Packages built with <tt>make</tt> can often implement
+ this by passing the <tt>-j</tt><var>n</var> option to
+ <tt>make</tt>.
+ </footnote>
+ If the package build system does not support parallel
+ builds, this string must be ignored. If the package
+ build system only supports a lower level of concurrency
+ than <var>n</var>, the package should be built using as
+ many parallel processes as the package build system
+ supports. It is up to the package maintainer to decide
+ whether the package build times are long enough and the
+ package build system is robust enough to make supporting
+ parallel builds worthwhile.
+ </item>
+ </taglist>
+ </p>
+
+ <p>
+ Unknown flags must be ignored by <file>debian/rules</file>.
+ </p>
+
+ <p>
+ The following makefile snippet is an example of how one may
+ implement the build options; you will probably have to
+ massage this example in order to make it work for your
+ package.
+ <example compact="compact">
+CFLAGS = -Wall -g
+INSTALL = install
+INSTALL_FILE = $(INSTALL) -p -o root -g root -m 644
+INSTALL_PROGRAM = $(INSTALL) -p -o root -g root -m 755
+INSTALL_SCRIPT = $(INSTALL) -p -o root -g root -m 755
+INSTALL_DIR = $(INSTALL) -p -d -o root -g root -m 755
+
+ifneq (,$(filter noopt,$(DEB_BUILD_OPTIONS)))
+ CFLAGS += -O0
+else
+ CFLAGS += -O2
+endif
+ifeq (,$(filter nostrip,$(DEB_BUILD_OPTIONS)))
+ INSTALL_PROGRAM += -s
+endif
+ifneq (,$(filter parallel=%,$(DEB_BUILD_OPTIONS)))
+ NUMJOBS = $(patsubst parallel=%,%,$(filter parallel=%,$(DEB_BUILD_OPTIONS)))
+ MAKEFLAGS += -j$(NUMJOBS)
+endif
+ </example>
+ </p>
+ </sect1>
</sect>
<!-- FIXME: section pkg-srcsubstvars is the same as substvars -->
<p>
Although binaries in the build tree should be compiled with
- debugging information by default, it can often be difficult
- to debug programs if they are also subjected to compiler
- optimization. For this reason, it is recommended to support
- the standardized environment
- variable <tt>DEB_BUILD_OPTIONS</tt>. This variable can
- contain several flags to change how a package is compiled
- and built.
- </p>
-
- <p>
- <taglist>
- <tag>noopt</tag>
- <item>
- The presence of this string means that the package
- should be compiled with a minimum of optimization.
- For C programs, it is best to add <tt>-O0</tt>
- to <tt>CFLAGS</tt> (although this is usually the
- default). Some programs might fail to build or run at
- this level of optimization; it may be necessary to
- use <tt>-O1</tt>, for example.
- </item>
- <tag>nostrip</tag>
- <item>
- This string means that the debugging symbols should
- not be stripped from the binary during installation,
- so that debugging information may be included in the package.
- </item>
- </taglist>
- </p>
-
- <p>
- The following makefile snippet is an example of how one may
- implement the build options; you will probably have to
- massage this example in order to make it work for your
- package.
- <example compact="compact">
-CFLAGS = -Wall -g
-INSTALL = install
-INSTALL_FILE = $(INSTALL) -p -o root -g root -m 644
-INSTALL_PROGRAM = $(INSTALL) -p -o root -g root -m 755
-INSTALL_SCRIPT = $(INSTALL) -p -o root -g root -m 755
-INSTALL_DIR = $(INSTALL) -p -d -o root -g root -m 755
-
-ifneq (,$(findstring noopt,$(DEB_BUILD_OPTIONS)))
-CFLAGS += -O0
-else
-CFLAGS += -O2
-endif
-ifeq (,$(findstring nostrip,$(DEB_BUILD_OPTIONS)))
-INSTALL_PROGRAM += -s
-endif
- </example>
+ debugging information by default, it can often be difficult to
+ debug programs if they are also subjected to compiler
+ optimization. For this reason, it is recommended to support the
+ standardized environment variable <tt>DEB_BUILD_OPTIONS</tt>
+ (see <ref id="debianrules-options">). This variable can contain
+ several flags to change how a package is compiled and built.
</p>
<p>
projects / debian / debian-policy.git / commitdiff