Package Creation Tutorial¶
This tutorial will walk you through the steps behind building a simple package installation script. We’ll focus on writing a package for mpileaks, an MPI debugging tool. By creating a package file we’re essentially giving Spack a recipe for how to build a particular piece of software. We’re describing some of the software’s dependencies, where to find the package, what commands and options are used to build the package from source, and more. Once we’ve specified a package’s recipe, we can ask Spack to build that package in many different ways.
This tutorial assumes you have a basic familiarity with some of the Spack commands, and that you have a working version of Spack installed. If not, we suggest looking at Spack’s Getting Started guide. This tutorial also assumes you have at least a beginner’s-level familiarity with Python.
Also note that this document is a tutorial. It can help you get started with packaging, but is not intended to be complete. See Spack’s Packaging Guide for more complete documentation on this topic.
Getting Started¶
A few things before we get started:
We’ll refer to the Spack installation location via the environment variable
SPACK_ROOT
. You should pointSPACK_ROOT
at wherever you have Spack installed.Add
$SPACK_ROOT/bin
to yourPATH
before you start.Make sure your
EDITOR
environment variable is set to your preferred text editor.We’ll be writing Python code as part of this tutorial. You can find successive versions of the Python code in
$SPACK_ROOT/lib/spack/docs/tutorial/examples
.
Creating the Package File¶
We will use a separate package repository for the tutorial. Package repositories allow you to separate sets of packages that take precedence over one another. We will use the tutorial repo that ships with Spack to avoid breaking the builtin Spack packages.
$ spack repo add $SPACK_ROOT/var/spack/repos/tutorial/
==> Added repo with namespace 'tutorial'.
Spack comes with a handy command to create a new package: spack create
.
This command is given the location of a package’s source code, downloads
the code, and sets up some basic packaging infrastructure for you. The
mpileaks source code can be found on GitHub, and here’s what happens when
we run spack create
on it:
$ spack create -t generic https://github.com/LLNL/mpileaks/releases/download/v1.0/mpileaks-1.0.tar.gz
==> This looks like a URL for mpileaks
==> Found 1 version of mpileaks:
1.0 https://github.com/LLNL/mpileaks/releases/download/v1.0/mpileaks-1.0.tar.gz
==> How many would you like to checksum? (default is 1, q to abort) 1
==> Downloading...
==> Fetching https://github.com/LLNL/mpileaks/releases/download/v1.0/mpileaks-1.0.tar.gz
############################################################################# 100.0%
==> Checksummed 1 version of mpileaks
==> Using specified package template: 'generic'
==> Created template for mpileaks package
==> Created package file: ~/spack/var/spack/repos/tutorial/packages/mpileaks/package.py
Spack should spawn a text editor with this file:
# Copyright 2013-2019 Lawrence Livermore National Security, LLC and other
# Spack Project Developers. See the top-level COPYRIGHT file for details.
#
# SPDX-License-Identifier: (Apache-2.0 OR MIT)
#
# This is a template package file for Spack. We've put "FIXME"
# next to all the things you'll want to change. Once you've handled
# them, you can save this file and test your package like this:
#
# spack install mpileaks
#
# You can edit this file again by typing:
#
# spack edit mpileaks
#
# See the Spack documentation for more information on packaging.
# If you submit this package back to Spack as a pull request,
# please first remove this boilerplate and all FIXME comments.
#
from spack import *
class Mpileaks(Package):
"""FIXME: Put a proper description of your package here."""
# FIXME: Add a proper url for your package's homepage here.
homepage = "http://www.example.com"
url = "https://github.com/LLNL/mpileaks/releases/download/v1.0/mpileaks-1.0.tar.gz"
version('1.0', sha256='2e34cc4505556d1c1f085758e26f2f8eea0972db9382f051b2dcfb1d7d9e1825')
# FIXME: Add dependencies if required.
# depends_on('foo')
def install(self, spec, prefix):
# FIXME: Unknown build system
make()
make('install')
Spack has created this file in
$SPACK_ROOT/var/spack/repos/tutorial/packages/mpileaks/package.py
. Take a
moment to look over the file. There’s a few placeholders that Spack has
created, which we’ll fill in as part of this tutorial:
We’ll document some information about this package in the comments.
We’ll fill in the dependency list for this package.
We’ll fill in some of the configuration arguments needed to build this package.
For the moment, exit your editor and let’s see what happens when we try to build this package:
$ spack install mpileaks
==> Installing mpileaks
==> Searching for binary cache of mpileaks
==> Warning: No Spack mirrors are currently configured
==> No binary for mpileaks found: installing from source
==> Fetching https://github.com/LLNL/mpileaks/releases/download/v1.0/mpileaks-1.0.tar.gz
############################################################################# 100.0%
==> Staging archive: ~/spack/var/spack/stage/mpileaks-1.0-sv75n3u5ev6mljwcezisz3slooozbbxu/mpileaks-1.0.tar.gz
==> Created stage in ~/spack/var/spack/stage/mpileaks-1.0-sv75n3u5ev6mljwcezisz3slooozbbxu
==> No patches needed for mpileaks
==> Building mpileaks [Package]
==> Executing phase: 'install'
==> Error: ProcessError: Command exited with status 2:
'make' '-j16'
1 error found in build log:
1 ==> Executing phase: 'install'
2 ==> 'make' '-j16'
>> 3 make: *** No targets specified and no makefile found. Stop.
See build log for details:
~/spack/var/spack/stage/mpileaks-1.0-sv75n3u5ev6mljwcezisz3slooozbbxu/spack-build-out.txt
This obviously didn’t work; we need to fill in the package-specific information. Specifically, Spack didn’t try to build any of mpileaks’ dependencies, nor did it use the proper configure arguments. Let’s start fixing things.
Package Documentation¶
We can bring the package.py
file back into our EDITOR
with the
spack edit
command:
$ spack edit mpileaks
Let’s remove some of the FIXME
comments, add links to the mpileaks
homepage, and document what mpileaks does. I’m also going to cut out the
Copyright clause at this point to keep this tutorial document shorter,
but you shouldn’t do that normally. The results of these changes can be
found in $SPACK_ROOT/lib/spack/docs/tutorial/examples/1.package.py
and are displayed below. Make these changes to your package.py
:
from spack import *
class Mpileaks(Package):
"""Tool to detect and report MPI objects like MPI_Requests and
MPI_Datatypes."""
homepage = "https://github.com/LLNL/mpileaks"
url = "https://github.com/LLNL/mpileaks/releases/download/v1.0/mpileaks-1.0.tar.gz"
version('1.0', sha256='2e34cc4505556d1c1f085758e26f2f8eea0972db9382f051b2dcfb1d7d9e1825')
# FIXME: Add dependencies if required.
# depends_on('foo')
def install(self, spec, prefix):
# FIXME: Unknown build system
make()
make('install')
We’ve filled in the comment that describes what this package does and added a link to its website. That won’t help us build yet, but it will allow Spack to provide some documentation on this package to other users:
$ spack info mpileaks
Package: mpileaks
Description:
Tool to detect and report MPI objects like MPI_Requests and
MPI_Datatypes.
Homepage: https://github.com/LLNL/mpileaks
Tags:
None
Preferred version:
1.0 https://github.com/LLNL/mpileaks/releases/download/v1.0/mpileaks-1.0.tar.gz
Safe versions:
1.0 https://github.com/LLNL/mpileaks/releases/download/v1.0/mpileaks-1.0.tar.gz
Variants:
None
Installation Phases:
install
Build Dependencies:
None
Link Dependencies:
None
Run Dependencies:
None
Virtual Packages:
None
As we fill in more information about this package the spack info
command
will become more informative. Now let’s start making this package build.
Dependencies¶
The mpileaks package depends on three other packages: mpi
,
adept-utils
, and callpath
. Let’s add those via the
depends_on
command in our package.py
(this version is in
$SPACK_ROOT/lib/spack/docs/tutorial/examples/2.package.py
):
from spack import *
class Mpileaks(Package):
"""Tool to detect and report MPI objects like MPI_Requests and
MPI_Datatypes."""
homepage = "https://github.com/LLNL/mpileaks"
url = "https://github.com/LLNL/mpileaks/releases/download/v1.0/mpileaks-1.0.tar.gz"
version('1.0', sha256='2e34cc4505556d1c1f085758e26f2f8eea0972db9382f051b2dcfb1d7d9e1825')
depends_on('mpi')
depends_on('adept-utils')
depends_on('callpath')
def install(self, spec, prefix):
# FIXME: Unknown build system
make()
make('install')
Now when we go to build mpileaks, Spack will fetch and build these
dependencies before building mpileaks. Note that the mpi dependency is a
different kind of beast than the adept-utils and callpath dependencies;
there is no mpi package available in Spack. Instead mpi is a virtual
dependency. Spack may satisfy that dependency by installing packages
such as openmpi
or mvapich2
. See the Packaging Guide for more
information on virtual dependencies.
Now when we try to install this package, a lot more happens:
$ spack install mpileaks
...
==> Successfully installed libdwarf from binary cache
[+] ~/spack/opt/spack/linux-ubuntu16.04-x86_64/gcc-5.4.0/libdwarf-20180129-p4jeflorwlnkoq2vpuyocwrbcht2ayak
==> Installing callpath
==> Searching for binary cache of callpath
==> Installing callpath from binary cache
==> Fetching file:///mirror/build_cache/linux-ubuntu16.04-x86_64/gcc-5.4.0/callpath-1.0.4/linux-ubuntu16.04-x86_64-gcc-5.4.0-callpath-1.0.4-empvyxdkc4j4pwg7gznwhbiumruey66x.spack
######################################################################## 100.0%
==> Successfully installed callpath from binary cache
[+] ~/spack/opt/spack/linux-ubuntu16.04-x86_64/gcc-5.4.0/callpath-1.0.4-empvyxdkc4j4pwg7gznwhbiumruey66x
==> Installing mpileaks
==> Searching for binary cache of mpileaks
==> No binary for mpileaks found: installing from source
==> Using cached archive: ~/spack/var/spack/cache/mpileaks/mpileaks-1.0.tar.gz
==> Staging archive: ~/spack/var/spack/stage/mpileaks-1.0-csoikctsalli4cdkkdk377gprkc472rb/mpileaks-1.0.tar.gz
==> Created stage in ~/spack/var/spack/stage/mpileaks-1.0-csoikctsalli4cdkkdk377gprkc472rb
==> No patches needed for mpileaks
==> Building mpileaks [Package]
==> Executing phase: 'install'
==> Error: ProcessError: Command exited with status 2:
'make' '-j16'
1 error found in build log:
1 ==> Executing phase: 'install'
2 ==> 'make' '-j16'
>> 3 make: *** No targets specified and no makefile found. Stop.
See build log for details:
~/spack/var/spack/stage/mpileaks-1.0-csoikctsalli4cdkkdk377gprkc472rb/mpileaks-1.0/spack-build-out.txt
Note that this command may take a while to run and produce more output if you don’t have an MPI already installed or configured in Spack.
Now Spack has identified and made sure all of our dependencies have been
built. It found the openmpi
package that will satisfy our mpi
dependency, and the callpath
and adept-utils
package to satisfy our
concrete dependencies.
Debugging Package Builds¶
Our mpileaks
package is still not building. It may be obvious to
many of you that we never ran the configure script. Let’s add a
call to configure()
to the top of the install routine. The resulting
package.py
is in $SPACK_ROOT/lib/spack/docs/tutorial/examples/3.package.py
:
from spack import *
class Mpileaks(Package):
"""Tool to detect and report MPI objects like MPI_Requests and
MPI_Datatypes."""
homepage = "https://github.com/LLNL/mpileaks"
url = "https://github.com/LLNL/mpileaks/releases/download/v1.0/mpileaks-1.0.tar.gz"
version('1.0', sha256='2e34cc4505556d1c1f085758e26f2f8eea0972db9382f051b2dcfb1d7d9e1825')
depends_on('mpi')
depends_on('adept-utils')
depends_on('callpath')
def install(self, spec, prefix):
configure()
make()
make('install')
If we re-run we still get errors:
$ spack install mpileaks
...
==> Installing mpileaks
==> Searching for binary cache of mpileaks
==> Finding buildcaches in /mirror/build_cache
==> No binary for mpileaks found: installing from source
==> Using cached archive: ~/spack/var/spack/cache/mpileaks/mpileaks-1.0.tar.gz
==> Staging archive: ~/spack/var/spack/stage/mpileaks-1.0-csoikctsalli4cdkkdk377gprkc472rb/mpileaks-1.0.tar.gz
==> Created stage in ~/spack/var/spack/stage/mpileaks-1.0-csoikctsalli4cdkkdk377gprkc472rb
==> No patches needed for mpileaks
==> Building mpileaks [Package]
==> Executing phase: 'install'
==> Error: ProcessError: Command exited with status 1:
'./configure'
1 error found in build log:
25 checking for ~/spack/opt/spack/linux-ubuntu16.04-x86_64/gcc-5.4.0/openmpi-3.1.3-3
njc4q5pqdpptq6jvqjrezkffwokv2sx/bin/mpicc... ~/spack/opt/spack/linux-ubuntu16.04-
x86_64/gcc-5.4.0/openmpi-3.1.3-3njc4q5pqdpptq6jvqjrezkffwokv2sx/bin/mpicc
26 Checking whether ~/spack/opt/spack/linux-ubuntu16.04-x86_64/gcc-5.4.0/openmpi-3.1
.3-3njc4q5pqdpptq6jvqjrezkffwokv2sx/bin/mpicc responds to '-showme:compile'... no
27 Checking whether ~/spack/opt/spack/linux-ubuntu16.04-x86_64/gcc-5.4.0/openmpi-3.1
.3-3njc4q5pqdpptq6jvqjrezkffwokv2sx/bin/mpicc responds to '-showme'... no
28 Checking whether ~/spack/opt/spack/linux-ubuntu16.04-x86_64/gcc-5.4.0/openmpi-3.1
.3-3njc4q5pqdpptq6jvqjrezkffwokv2sx/bin/mpicc responds to '-compile-info'... no
29 Checking whether ~/spack/opt/spack/linux-ubuntu16.04-x86_64/gcc-5.4.0/openmpi-3.1
.3-3njc4q5pqdpptq6jvqjrezkffwokv2sx/bin/mpicc responds to '-show'... no
30 ./configure: line 4809: Echo: command not found
>> 31 configure: error: unable to locate adept-utils installation
See build log for details:
~/spack/var/spack/stage/mpileaks-1.0-csoikctsalli4cdkkdk377gprkc472rb/mpileaks-1.0/spack-build-out.txt
Again, the problem may be obvious. But let’s pretend we’re not all experienced Autotools developers and use this opportunity to spend some time debugging. We have a few options that can tell us about what’s going wrong:
As per the error message, Spack has given us a spack-build-out.txt
debug
log:
==> Executing phase: 'install'
==> './configure'
checking metadata... no
checking installation directory variables... yes
checking for a BSD-compatible install... /usr/bin/install -c
checking whether build environment is sane... yes
checking for a thread-safe mkdir -p... /bin/mkdir -p
checking for gawk... gawk
checking whether make sets $(MAKE)... yes
checking for gcc... /home/spack1/spack/lib/spack/env/gcc/gcc
checking for C compiler default output file name... a.out
checking whether the C compiler works... yes
checking whether we are cross compiling... no
checking for suffix of executables...
checking for suffix of object files... o
checking whether we are using the GNU C compiler... yes
checking whether /home/spack1/spack/lib/spack/env/gcc/gcc accepts -g... yes
checking for /home/spack1/spack/lib/spack/env/gcc/gcc option to accept ISO C89... none needed
checking for style of include used by make... GNU
checking dependency style of /home/spack1/spack/lib/spack/env/gcc/gcc... gcc3
checking whether /home/spack1/spack/lib/spack/env/gcc/gcc and cc understand -c and -o together... yes
checking whether we are using the GNU C++ compiler... yes
checking whether /home/spack1/spack/lib/spack/env/gcc/g++ accepts -g... yes
checking dependency style of /home/spack1/spack/lib/spack/env/gcc/g++... gcc3
checking for /home/spack1/spack/opt/spack/linux-ubuntu16.04-x86_64/gcc-5.4.0/openmpi-3.0.0-yo5qkfvumpmgmvlbalqcadu46j5bd52f/bin/mpicc... /home/spack1/spack/opt/spack/linux-ubuntu16.04-x86_64/gcc-5.4.0/openmpi-3.0.0-yo5qkfvumpmgmvlbalqcadu46j5bd52f/bin/mpicc
Checking whether /home/spack1/spack/opt/spack/linux-ubuntu16.04-x86_64/gcc-5.4.0/openmpi-3.0.0-yo5qkfvumpmgmvlbalqcadu46j5bd52f/bin/mpicc responds to '-showme:compile'... yes
configure: error: unable to locate adept-utils installation
This gives us the output from the build, and mpileaks isn’t
finding its adept-utils
package. Spack has
automatically added the include and library directories of
adept-utils
to the compiler’s search path, but some packages like
mpileaks can sometimes be picky and still want things spelled out on
their command line. But let’s continue to pretend we’re not experienced
developers, and explore some other debugging paths:
We can also enter the build area and try to manually run the build:
$ spack build-env mpileaks bash
$ spack cd mpileaks
The spack build-env
command spawned a new shell that contains the same
environment that Spack used to build the mpileaks package (you can
substitute bash for your favorite shell). The spack cd
command
changed our working dirctory to the last attempted build for mpileaks.
From here we can manually re-run the build:
$ ./configure
checking metadata... no
checking installation directory variables... yes
checking for a BSD-compatible install... /usr/bin/install -c
checking whether build environment is sane... yes
checking for a thread-safe mkdir -p... /bin/mkdir -p
checking for gawk... gawk
checking whether make sets $(MAKE)... yes
checking for gcc... /home/spack1/spack/lib/spack/env/gcc/gcc
checking for C compiler default output file name... a.out
checking whether the C compiler works... yes
checking whether we are cross compiling... no
checking for suffix of executables...
checking for suffix of object files... o
checking whether we are using the GNU C compiler... yes
checking whether /home/spack1/spack/lib/spack/env/gcc/gcc accepts -g... yes
checking for /home/spack1/spack/lib/spack/env/gcc/gcc option to accept ISO C89... none needed
checking for style of include used by make... GNU
checking dependency style of /home/spack1/spack/lib/spack/env/gcc/gcc... gcc3
checking whether /home/spack1/spack/lib/spack/env/gcc/gcc and cc understand -c and -o together... yes
checking whether we are using the GNU C++ compiler... yes
checking whether /home/spack1/spack/lib/spack/env/gcc/g++ accepts -g... yes
checking dependency style of /home/spack1/spack/lib/spack/env/gcc/g++... gcc3
checking for /home/spack1/spack/opt/spack/linux-ubuntu16.04-x86_64/gcc-5.4.0/openmpi-3.0.0-yo5qkfvumpmgmvlbalqcadu46j5bd52f/bin/mpicc... /home/spack1/spack/opt/spack/linux-ubuntu16.04-x86_64/gcc-5.4.0/openmpi-3.0.0-yo5qkfvumpmgmvlbalqcadu46j5bd52f/bin/mpicc
Checking whether /home/spack1/spack/opt/spack/linux-ubuntu16.04-x86_64/gcc-5.4.0/openmpi-3.0.0-yo5qkfvumpmgmvlbalqcadu46j5bd52f/bin/mpicc responds to '-showme:compile'... yes
configure: error: unable to locate adept-utils installation
We’re seeing the same error, but now we’re in a shell where we can run
the command ourselves and debug as needed. We could, for example, run
./configure --help
to see what options we can use to specify
dependencies.
We can use the exit
command to leave the shell spawned by spack
build-env
.
Specifying Configure Arguments¶
Let’s add the configure arguments to the mpileaks’ package.py
. This
version can be found in
$SPACK_ROOT/lib/spack/docs/tutorial/examples/4.package.py
:
from spack import *
class Mpileaks(Package):
"""Tool to detect and report MPI objects like MPI_Requests and
MPI_Datatypes."""
homepage = "https://github.com/LLNL/mpileaks"
url = "https://github.com/LLNL/mpileaks/releases/download/v1.0/mpileaks-1.0.tar.gz"
version('1.0', sha256='2e34cc4505556d1c1f085758e26f2f8eea0972db9382f051b2dcfb1d7d9e1825')
depends_on('mpi')
depends_on('adept-utils')
depends_on('callpath')
def install(self, spec, prefix):
configure('--prefix={0}'.format(prefix),
'--with-adept-utils={0}'.format(spec['adept-utils'].prefix),
'--with-callpath={0}'.format(spec['callpath'].prefix))
make()
make('install')
This is all we need for a working mpileaks package! If we install now we’ll see:
$ spack install mpileaks
...
==> Installing mpileaks
==> Searching for binary cache of mpileaks
==> Finding buildcaches in /mirror/build_cache
==> No binary for mpileaks found: installing from source
==> Using cached archive: ~/spack/var/spack/cache/mpileaks/mpileaks-1.0.tar.gz
==> Staging archive: ~/spack/var/spack/stage/mpileaks-1.0-csoikctsalli4cdkkdk377gprkc472rb/mpileaks-1.0.tar.gz
==> Created stage in ~/spack/var/spack/stage/mpileaks-1.0-csoikctsalli4cdkkdk377gprkc472rb
==> No patches needed for mpileaks
==> Building mpileaks [Package]
==> Executing phase: 'install'
==> Successfully installed mpileaks
Fetch: 0.00s. Build: 9.41s. Total: 9.41s.
[+] ~/spack/opt/spack/linux-ubuntu16.04-x86_64/gcc-5.4.0/mpileaks-1.0-csoikctsalli4cdkkdk377gprkc472rb
There are some special circumstances in this package that are worth highlighting.
Normally, Spack would have automatically detected that mpileaks was an
Autotools-based package when we ran spack create
and made it an AutoToolsPackage
class (except we added the -t generic
option to skip this). Instead of
a full install routine we would have just written:
def configure_args(self):
return [
'--with-adept-utils={0}'.format(self.spec['adept-utils'].prefix),
'--with-callpath={0}'.format(self.spec['callpath'].prefix)
]
Similarly, if this had been a CMake-based package we
would have been filling in a cmake_args
function instead of
configure_args
. There are similar default package types for
many build environments that will be discussed later in the tutorial.
Variants¶
We have a successful mpileaks build, but let’s take some time to improve
it. mpileaks
has a build-time option to truncate parts of the stack
that it walks. Let’s add a variant to allow users to set this when they
build mpileaks with Spack.
To do this, we’ll add a variant to our package, as per the following (see
$SPACK_ROOT/lib/spack/docs/tutorial/examples/5.package.py
):
from spack import *
class Mpileaks(Package):
"""Tool to detect and report MPI objects like MPI_Requests and
MPI_Datatypes."""
homepage = "https://github.com/LLNL/mpileaks"
url = "https://github.com/LLNL/mpileaks/releases/download/v1.0/mpileaks-1.0.tar.gz"
version('1.0', sha256='2e34cc4505556d1c1f085758e26f2f8eea0972db9382f051b2dcfb1d7d9e1825')
variant('stackstart', values=int, default=0,
description='Specify the number of stack frames to truncate')
depends_on('mpi')
depends_on('adept-utils')
depends_on('callpath')
def install(self, spec, prefix):
stackstart = int(spec.variants['stackstart'].value)
args = [
'--prefix={0}'.format(prefix),
'--with-adept-utils={0}'.format(spec['adept-utils'].prefix),
'--with-callpath={0}'.format(spec['callpath'].prefix),
]
if stackstart:
args.extend([
'--with-stack-start-c={0}'.format(stackstart),
'--with-stack-start-fortran={0}'.format(stackstart)
])
configure(*args)
make()
make('install')
We’ve added the variant stackstart
, and given it a default value of
0
. If we install now we can see the stackstart variant added to the
configure line (output truncated for length):
$ spack install --verbose mpileaks stackstart=4
...
==> Installing mpileaks
==> Searching for binary cache of mpileaks
==> Finding buildcaches in /mirror/build_cache
==> No binary for mpileaks found: installing from source
==> Using cached archive: ~/spack/var/spack/cache/mpileaks/mpileaks-1.0.tar.gz
==> Staging archive: ~/spack/var/spack/stage/mpileaks-1.0-meufjojkxve3l7rci2mbud3faidgplto/mpileaks-1.0.tar.gz
==> Created stage in ~/spack/var/spack/stage/mpileaks-1.0-meufjojkxve3l7rci2mbud3faidgplto
==> No patches needed for mpileaks
==> Building mpileaks [Package]
==> Executing phase: 'install'
==> './configure' '--prefix=~/spack/opt/spack/linux-ubuntu16.04-x86_64/gcc-5.4.0/mpileaks-1.0-meufjojkxve3l7rci2mbud3faidgplto' '--with-adept-utils=~/spack/opt/spack/linux-ubuntu16.04-x86_64/gcc-5.4.0/adept-utils-1.0.1-7tippnvo5g76wpijk7x5kwfpr3iqiaen' '--with-callpath=~/spack/opt/spack/linux-ubuntu16.04-x86_64/gcc-5.4.0/callpath-1.0.4-empvyxdkc4j4pwg7gznwhbiumruey66x' '--with-stack-start-c=4' '--with-stack-start-fortran=4'
The Spec Object¶
This tutorial has glossed over a few important features, which weren’t
too relevant for mpileaks but may be useful for other packages. There
were several places we reference the self.spec
object. This is a
powerful class for querying information about what we’re building. For
example, you could use the spec to query information about how a
package’s dependencies were built, or what compiler was being used, or
what version of a package is being installed. Full documentation can be
found in the Packaging Guide,
but here’s some quick snippets with common queries:
Am I building
mpileaks
version1.1
or greater?
if self.spec.satisfies('@1.1:'):
# Do things needed for 1.1+
Is
openmpi
the MPI I’m building with?
if self.spec['mpi'].name == 'openmpi':
# Do openmpi things
Am I building with
gcc
version less than5.0.0
:
if self.spec.satisfies('%gcc@:5.0.0'):
# Add arguments specific to gcc's earlier than 5.0.0
Am I building with the
debug
variant:
if self.spec.satisfies('+debug'):
# Add -g option to configure flags
Is my
dyninst
dependency greater than version8.0
?
if self.spec['dyninst'].satisfies('@8.0:'):
# Use newest dyninst options
More examples can be found in the thousands of packages already added to
Spack in $SPACK_ROOT/var/spack/repos/builtin/packages
.
Good Luck!
To ensure that future sections of the tutorial run properly, please uninstall mpileaks and remove the tutorial repo from your configuration.
$ spack uninstall -ay mpileaks
$ spack repo remove tutorial
$ rm -rf $SPACK_ROOT/var/spack/repos/tutorial/packages/mpileaks