scons-utils.eclass

Name

scons-utils.eclass -- helper functions to deal with SCons buildsystem

Description

This eclass provides a set of function to help developers sanely call dev-util/scons and pass parameters to it.

As of dev-util/scons-3.0.1-r100, SCons supports Python 3. Since SCons* files in build systems are written as Python, all packages need to explicitly verify which versions of Python are supported and use appropriate Python suite eclass to select the implementation. The eclass needs to be inherited before scons-utils, and scons-utils will automatically take advantage of it. For more details, please see: https://wiki.gentoo.org/wiki/Project:Python/scons-utils_integration

Please note that SCons is more like a 'build system creation kit', and requires a lot of upstream customization to be used sanely. You will often need to request fixes upstream and/or patch the build system. In particular:

1. There are no 'standard' variables. To respect CC, CXX, CFLAGS, CXXFLAGS, CPPFLAGS, LDFLAGS, upstream needs to define appropriate variables explicitly. In some cases, upstreams respect envvars, in others you need to pass them as options.

2. SCons scrubs out environment by default and replaces it with some pre-defined values. To respect environment variables such as PATH, Upstreams need to explicitly get them from os.environ and copy them to the build environment.

Supported EAPIs

0 1 2 3 4 5 6 7

Example

PYTHON_COMPAT=( python2_7 )
inherit python-any-r1 scons-utils toolchain-funcs

EAPI=5

src_configure() {
      MYSCONS=(
              CC="$(tc-getCC)"
      ENABLE_NLS=$(usex nls)
      )
}

src_compile() {
      escons "${MYSCONS[@]}"
}

src_install() {
      # note: this can be DESTDIR, INSTALL_ROOT, ... depending on package
      escons "${MYSCONS[@]}" DESTDIR="${D}" install
}

Functions

escons [<args>...]

Call scons, passing the supplied arguments. Like emake, this function does die on failure in EAPI 4. Respects nonfatal in EAPI 6 and newer.

use_scons <use-flag> [var-name] [var-opt-true] [var-opt-false]

DEPRECATED, EAPI 0..5 ONLY: use usex instead

Output a SCons parameter with value depending on the USE flag state. If the USE flag is set, output <var-name>=<var-opt-true>; otherwise <var-name>=<var-opt-false>.

If <var-name> is omitted, <use-flag> will be used instead. However, if <use-flag> starts with an exclamation mark (!flag), 'no' will be prepended to the name (e.g. noflag).

If <var-opt-true> and/or <var-opt-false> are omitted, ${USE_SCONS_TRUE} and/or ${USE_SCONS_FALSE} will be used instead.

Variables

SCONS_MIN_VERSION

The minimal version of SCons required for the build to work.

SCONSOPTS (USER VARIABLE)

The default set of options to pass to scons. Similar to MAKEOPTS, supposed to be set in make.conf. If unset, escons() will use cleaned up MAKEOPTS instead.

EXTRA_ESCONS (USER VARIABLE)

The additional parameters to pass to SCons whenever escons() is used. Much like EXTRA_EMAKE, this is not supposed to be used in make.conf and not in ebuilds!

USE_SCONS_TRUE ?= 1

DEPRECATED: use usex instead

The default value for truth in scons-use() (1 by default).

USE_SCONS_FALSE ?= 0

DEPRECATED: use usex instead

The default value for false in scons-use() (0 by default).

Function Variables

myesconsargs

DEPRECATED, EAPI 0..5 ONLY: pass options to escons instead

List of package-specific options to pass to all SCons calls. Supposed to be set in src_configure().

Maintainers

mgorny@gentoo.org

Reporting Bugs

Please report bugs via https://bugs.gentoo.org/