We'd like to use a consistent checksum scheme everywhere so that we can:
a) incorporate archive checksums into our specs and have a
consistent hashing algorithm across all specs.
b) index mirrors with a consistent type of checksum, and not one that
is dependent on how spack packages are written.
- [x] convert existing md5, sha224, sha512, sha1 checksums to sha256
- remove the old LGPL license headers from all files in Spack
- add SPDX headers to all files
- core and most packages are (Apache-2.0 OR MIT)
- a very small number of remaining packages are LGPL-2.1-only
The following improvements are made to cxx standard support
(e.g. compiler.cxxNN_flag functions) in compilers:
* Add cxx98_flag property
* Add support for throwing an exception when a flag is not supported (previously
if a flag was not supported the application was terminated with tty.die)
* The name of the flag associated with e.g. c++14 standard support changes for
different compiler versions (e.g. c++1y vs c++14). This makes a few corrections
on what flag to return for which version.
* Added tests to confirm that versions report expected flags for various c++
standards (or raise an exception for versions that don't provide a given cxx
standard)
Note that if a given cxx standard is the default, the associated flag property will
return ""; cxx98 is assumed to be the default standard so this is the behavior for
the associated property in the base compiler class.
Package changes:
* Improvements to the boost spec to take advantage of the improved standard
flag facility.
* Update the clingo spec to catch the new exception rather than look for an
empty flag to indicate non-support (which is not part of the compiler flag API)
