mvapich2: added version 2.3rc1 + variant to use alloca if available (#7595)

* mvapich2: added version 2.3rc1 + variant to use alloca if available

* mvapich2: removed version 1.9 + cleaned recipe

var/spack/repos/builtin/packages/mvapich2/ad_lustre_rwcontig_open_source.patch

@@ -1,11 +0,0 @@
---- a/src/mpi/romio/adio/ad_lustre/ad_lustre_rwcontig.c	2013-12-10 12:05:44.806417000 -0800
-+++ b/src/mpi/romio/adio/ad_lustre/ad_lustre_rwcontig.c	2013-12-10 11:53:03.295622000 -0800
-@@ -8,7 +8,7 @@
-  *   Copyright (C) 2008 Sun Microsystems, Lustre group
-  */
- 
--#define _XOPEN_SOURCE 600
-+//#define _XOPEN_SOURCE 600
- #include <stdlib.h>
- #include <malloc.h>
- #include "ad_lustre.h"

var/spack/repos/builtin/packages/mvapich2/package.py

@@ -41,20 +41,16 @@ class Mvapich2(AutotoolsPackage):
     url = "http://mvapich.cse.ohio-state.edu/download/mvapich/mv2/mvapich2-2.2.tar.gz"
     list_url = "http://mvapich.cse.ohio-state.edu/downloads/"
 
-    # Newer alpha release
+    version('2.3rc1', '386d79ae36b2136d203826465ad8b6cc')
     version('2.3a', '87c3fbf8a755b53806fa9ecb21453445')
 
     # Prefer the latest stable release
     version('2.2', '939b65ebe5b89a5bc822cdab0f31f96e', preferred=True)
     version('2.1', '0095ceecb19bbb7fb262131cb9c2cdd6')
     version('2.0', '9fbb68a4111a8b6338e476dc657388b4')
-    version('1.9', '5dc58ed08fd3142c260b70fe297e127c')
-
-    patch('ad_lustre_rwcontig_open_source.patch', when='@1.9')
 
     provides('mpi')
-    provides('mpi@:2.2', when='@1.9')  # MVAPICH2-1.9 supports MPI 2.2
-    provides('mpi@:3.0', when='@2.0:')  # MVAPICH2-2.0 supports MPI 3.0
+    provides('mpi@:3.0')
 
     variant('debug', default=False,
             description='Enable debug info and error messages at run-time')
@@ -103,6 +99,12 @@ class Mvapich2(AutotoolsPackage):
         )
     )
 
+    variant(
+        'alloca',
+        default=False,
+        description='Use alloca to allocate temporary memory if available'
+    )
+
     depends_on('bison', type='build')
     depends_on('libpciaccess', when=(sys.platform != 'darwin'))
     depends_on('cuda', when='+cuda')
@@ -111,13 +113,6 @@ class Mvapich2(AutotoolsPackage):
         'mpicc', 'mpicxx', 'mpif77', 'mpif90', 'mpifort', relative_root='bin'
     )
 
-    def url_for_version(self, version):
-        base_url = "http://mvapich.cse.ohio-state.edu/download"
-        if version < Version('2.0'):
-            return "%s/mvapich2/mv2/mvapich2-%s.tar.gz" % (base_url, version)
-        else:
-            return "%s/mvapich/mv2/mvapich2-%s.tar.gz"  % (base_url, version)
-
     @property
     def process_manager_options(self):
         spec = self.spec
@@ -130,16 +125,10 @@ def process_manager_options(self):
 
         # See: http://slurm.schedmd.com/mpi_guide.html#mvapich2
         if 'process_managers=slurm' in spec:
-            if self.version > Version('2.0'):
             opts = [
                 '--with-pmi=pmi2',
                 '--with-pm=slurm'
             ]
-            else:
-                opts = [
-                    '--with-pmi=slurm',
-                    '--with-pm=no'
-                ]
 
         return opts
 
@@ -165,7 +154,7 @@ def network_options(self):
 
     def setup_environment(self, spack_env, run_env):
         spec = self.spec
-        if 'process_managers=slurm' in spec and spec.satisfies('@2.0:'):
+        if 'process_managers=slurm' in spec:
             run_env.set('SLURM_MPI_TYPE', 'pmi2')
 
     def setup_dependent_environment(self, spack_env, run_env, dependent_spec):
@@ -206,12 +195,15 @@ def configure_args(self):
             '--enable-shared',
             '--enable-romio',
             '-disable-silent-rules',
+            '--disable-new-dtags',
             '--enable-fortran=all',
             "--enable-threads={0}".format(spec.variants['threads'].value),
             "--with-ch3-rank-bits={0}".format(
                 spec.variants['ch3_rank_bits'].value),
         ]
 
+        args.extend(self.enable_or_disable('alloca'))
+
         if '+debug' in self.spec:
             args.extend([
                 '--disable-fast',