openmpi: updated package (#7574)

Modifications:
* Added zlib dependency, starting from version 3.0.0
* Added memchecker support  for debugging
* Remove mpirun and similar links if slurm is selected as a scheduler

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

@@ -201,6 +201,17 @@ class Openmpi(AutotoolsPackage):
     variant('cuda', default=False, description='Enable CUDA support')
     variant('ucx', default=False, description='Enable UCX support')
     variant('pmi', default=False, description='Enable PMI support')
+    # Adding support to build a debug version of OpenMPI that activates
+    # Memchecker, as described here:
+    #
+    # https://www.open-mpi.org/faq/?category=debugging#memchecker_what
+    #
+    # This option degrades run-time support, and thus is disabled by default
+    variant(
+        'memchecker',
+        default=False,
+        description='Memchecker support for debugging [degrades performance]'
+    )
 
     provides('mpi')
     provides('mpi@:2.2', when='@1.6.5')
@@ -218,6 +229,8 @@ class Openmpi(AutotoolsPackage):
     depends_on('java', when='+java')
     depends_on('sqlite', when='+sqlite3@:1.11')
     depends_on('ucx', when='+ucx')
+    depends_on('zlib', when='@3.0.0:')
+    depends_on('valgrind~mpi', when='+memchecker')
 
     conflicts('+cuda', when='@:1.6')  # CUDA support was added in 1.7
     conflicts('fabrics=psm2', when='@:1.8')  # PSM2 support was added in 1.10.0
@@ -320,6 +333,9 @@ def configure_args(self):
             # for Open-MPI 2.0:, C++ bindings are disabled by default.
             config_args.extend(['--enable-mpi-cxx'])
 
+        if spec.satisfies('@3.0.0:', strict=True):
+            config_args.append('--with-zlib={0}'.format(spec['zlib'].prefix))
+
         # Fabrics
         config_args.extend(self.with_or_without('fabrics'))
         # Schedulers
@@ -327,6 +343,13 @@ def configure_args(self):
         # PMI
         config_args.extend(self.with_or_without('pmi'))
 
+        config_args.extend(self.enable_or_disable('memchecker'))
+        if spec.satisfies('+memchecker', strict=True):
+            config_args.extend([
+                '--enable-debug',
+                '--with-valgrind={0}'.format(spec['valgrind'].prefix),
+            ])
+
         # Hwloc support
         if spec.satisfies('@1.5.2:'):
             config_args.append('--with-hwloc={0}'.format(spec['hwloc'].prefix))
@@ -398,3 +421,18 @@ def configure_args(self):
             config_args.append('--without-ucx')
 
         return config_args
+
+    @run_after('install')
+    def delete_mpirun_mpiexec(self):
+        # The preferred way to run an application when Slurm is the
+        # scheduler is to let Slurm manage process spawning via PMI.
+        #
+        # Deleting the links to orterun avoids users running their
+        # applications via mpirun or mpiexec, and leaves srun as the
+        # only sensible choice (orterun is still present, but normal
+        # users don't know about that).
+        if '@1.6: schedulers=slurm' in self.spec:
+            os.remove(self.prefix.bin.mpirun)
+            os.remove(self.prefix.bin.mpiexec)
+            os.remove(self.prefix.bin.shmemrun)
+            os.remove(self.prefix.bin.oshrun)