Merge pull request #882 from davydden/openmp_compiler_flag

Compiler::openmp_flag()

lib/spack/docs/packaging_guide.rst

@@ -1831,6 +1831,25 @@ successfully find ``libdwarf.h`` and ``libdwarf.so``, without the
 packager having to provide ``--with-libdwarf=/path/to/libdwarf`` on
 the command line.
 
+Compiler flags
+~~~~~~~~~~~~~~
+In rare circumstances such as compiling and running small unit tests, a package
+developer may need to know what are the appropriate compiler flags to enable
+features like ``OpenMP``, ``c++11``, ``c++14`` and alike. To that end the
+compiler classes in ``spack`` implement the following _properties_ :
+``openmp_flag``, ``cxx11_flag``, ``cxx14_flag``, which can be accessed in a
+package by ``self.compiler.cxx11_flag`` and alike. Note that the implementation
+is such that if a given compiler version does not support this feature, an
+error will be produced. Therefore package developers can also use these properties
+to assert that a compiler supports the requested feature. This is handy when a
+package supports additional variants like
+
+.. code-block:: python
+
+   variant('openmp', default=True, description="Enable OpenMP support.")
+
+
+
 Message Parsing Interface (MPI)
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 It is common for high performance computing software/packages to use ``MPI``.

lib/spack/spack/compiler.py

@@ -94,12 +94,6 @@ class Compiler(object):
     # Names of generic arguments used by this compiler
     arg_rpath   = '-Wl,-rpath,%s'
 
-    # argument used to get C++11 options
-    cxx11_flag = "-std=c++11"
-
-    # argument used to get C++14 options
-    cxx14_flag = "-std=c++1y"
-
 
     def __init__(self, cspec, cc, cxx, f77, fc):
         def check(exe):
@@ -120,6 +114,37 @@ def check(exe):
     def version(self):
         return self.spec.version
 
+    # This property should be overridden in the compiler subclass if
+    # OpenMP is supported by that compiler
+    @property
+    def openmp_flag(self):
+        # If it is not overridden, assume it is not supported and warn the user
+        tty.die("The compiler you have chosen does not currently support OpenMP.",
+                "If you think it should, please edit the compiler subclass and",
+                "submit a pull request or issue.")
+
+
+    # This property should be overridden in the compiler subclass if
+    # C++11 is supported by that compiler
+    @property
+    def cxx11_flag(self):
+        # If it is not overridden, assume it is not supported and warn the user
+        tty.die("The compiler you have chosen does not currently support C++11.",
+                "If you think it should, please edit the compiler subclass and",
+                "submit a pull request or issue.")
+
+
+    # This property should be overridden in the compiler subclass if
+    # C++14 is supported by that compiler
+    @property
+    def cxx14_flag(self):
+        # If it is not overridden, assume it is not supported and warn the user
+        tty.die("The compiler you have chosen does not currently support C++14.",
+                "If you think it should, please edit the compiler subclass and",
+                "submit a pull request or issue.")
+
+
+
     #
     # Compiler classes have methods for querying the version of
     # specific compiler executables.  This is used when discovering compilers.

lib/spack/spack/compilers/clang.py

@@ -26,6 +26,8 @@
 import spack.compiler as cpr
 from spack.compiler import *
 from spack.util.executable import *
+import llnl.util.tty as tty
+from spack.version import ver
 
 class Clang(Compiler):
     # Subclasses use possible names of C compiler
@@ -47,6 +49,29 @@ class Clang(Compiler):
                    'f77' : 'f77',
                    'fc'  : 'f90' }
 
+    @property
+    def is_apple(self):
+        ver_string = str(self.version)
+        return ver_string.endswith('-apple')
+
+    @property
+    def openmp_flag(self):
+        if self.is_apple:
+            tty.die("Clang from Apple does not support Openmp yet.")
+        else:
+            return "-fopenmp"
+
+    @property
+    def cxx11_flag(self):
+        if self.is_apple:
+            # FIXME: figure out from which version Apple's clang supports c++11
+            return "-std=c++11"
+        else:
+            if self.version < ver('3.3'):
+                tty.die("Only Clang 3.3 and above support c++11.")
+            else:
+                return "-std=c++11"
+
     @classmethod
     def default_version(self, comp):
         """The '--version' option works for clang compilers.

lib/spack/spack/compilers/gcc.py

@@ -49,6 +49,10 @@ class Gcc(Compiler):
                   'f77' : 'gcc/gfortran',
                   'fc'  : 'gcc/gfortran' }
 
+    @property
+    def openmp_flag(self):
+        return "-fopenmp"
+
     @property
     def cxx11_flag(self):
         if self.version < ver('4.3'):

lib/spack/spack/compilers/intel.py

@@ -23,6 +23,8 @@
 # Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 ##############################################################################
 from spack.compiler import *
+import llnl.util.tty as tty
+from spack.version import ver
 
 class Intel(Compiler):
     # Subclasses use possible names of C compiler
@@ -43,6 +45,13 @@ class Intel(Compiler):
                    'f77' : 'intel/ifort',
                    'fc'  : 'intel/ifort' }
 
+    @property
+    def openmp_flag(self):
+        if self.version < ver('16.0'):
+            return "-openmp"
+        else:
+            return "-qopenmp"
+
     @property
     def cxx11_flag(self):
         if self.version < ver('11.1'):
@@ -68,5 +77,3 @@ def default_version(cls, comp):
         """
         return get_compiler_version(
             comp, '--version', r'\((?:IFORT|ICC)\) ([^ ]+)')
-
-

lib/spack/spack/compilers/nag.py

@@ -1,4 +1,5 @@
 from spack.compiler import *
+import llnl.util.tty as tty
 
 class Nag(Compiler):
     # Subclasses use possible names of C compiler
@@ -20,6 +21,16 @@ class Nag(Compiler):
                    'f77' : 'nag/nagfor',
                    'fc'  : 'nag/nagfor' }
 
+    @property
+    def openmp_flag(self):
+        return "-openmp"
+
+    @property
+    def cxx11_flag(self):
+        # NAG does not have a C++ compiler
+        # However, it can be mixed with a compiler that does support it
+        return "-std=c++11"
+
     @classmethod
     def default_version(self, comp):
         """The '-V' option works for nag compilers.

lib/spack/spack/compilers/pgi.py

@@ -23,6 +23,7 @@
 # Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 ##############################################################################
 from spack.compiler import *
+import llnl.util.tty as tty
 
 class Pgi(Compiler):
     # Subclasses use possible names of C compiler
@@ -43,6 +44,15 @@ class Pgi(Compiler):
                    'f77' : 'pgi/pgfortran',
                    'fc'  : 'pgi/pgfortran' }
 
+    @property
+    def openmp_flag(self):
+        return "-mp"
+
+    @property
+    def cxx11_flag(self):
+        return "-std=c++11"
+
+
     @classmethod
     def default_version(cls, comp):
         """The '-V' option works for all the PGI compilers.
@@ -54,4 +64,3 @@ def default_version(cls, comp):
         """
         return get_compiler_version(
             comp, '-V', r'pg[^ ]* ([^ ]+) \d\d\d?-bit target')
-

lib/spack/spack/compilers/xl.py

@@ -24,6 +24,8 @@
 # Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 ##############################################################################
 from spack.compiler import *
+import llnl.util.tty as tty
+from spack.version import ver
 
 class Xl(Compiler):
     # Subclasses use possible names of C compiler
@@ -44,6 +46,10 @@ class Xl(Compiler):
                    'f77' : 'xl/xlf',
                    'fc'  : 'xl/xlf90' }
 
+    @property
+    def openmp_flag(self):
+        return "-qsmp=omp"
+
     @property
     def cxx11_flag(self):
         if self.version < ver('13.1'):