Implemented compiler concretization policy.

5 files changed, 91 insertions, 41 deletions

diff --git a/lib/spack/spack/cmd/compilers.py b/lib/spack/spack/cmd/compilers.py
index 5658263c26..8267ecbd6b 100644
--- a/lib/spack/spack/cmd/compilers.py
+++ b/lib/spack/spack/cmd/compilers.py
@@ -34,7 +34,7 @@ description = "List available compilers"
 def compilers(parser, args):
     tty.msg("Available compilers")
 
-    index = index_by(spack.compilers.supported_compilers(), 'name')
+    index = index_by(spack.compilers.available_compilers(), 'name')
     for name, compilers in index.items():
         tty.hline(name, char='-', color=spack.spec.compiler_color)
         colify(compilers, indent=4)
diff --git a/lib/spack/spack/compilers/__init__.py b/lib/spack/spack/compilers/__init__.py
index 4bfb855d94..2b97cd1036 100644
--- a/lib/spack/spack/compilers/__init__.py
+++ b/lib/spack/spack/compilers/__init__.py
@@ -27,27 +27,34 @@
 #
 from llnl.util.lang import memoized, list_modules
 
+import spack
 import spack.spec
 from spack.util.executable import which
 
-
-
 @memoized
 def supported_compilers():
-    """Return a list of compiler types supported by Spack."""
+    """Return a list of names of compilers supported by Spack.
+
+       See available_compilers() to get a list of all the available
+       versions of supported compilers.
+    """
     return sorted(c for c in list_modules(spack.compilers_path))
 
 
-def supported(compiler_spec):
-    """Test if a particular compiler is supported."""
-    if isinstance(compiler_spec, spack.spec.Compiler):
-        return compiler_spec.name in supported_compilers()
+def available_compilers():
+    """Return a list of specs for all the compiler versions currently
+       available to build with.  These are instances of
+       spack.spec.Compiler.
+    """
+    return [spack.spec.Compiler(c)
+            for c in list_modules(spack.compiler_version_path)]
 
-    elif isinstance(compiler_spec, basestring):
-        return compiler_spec in supported_compilers()
 
-    else:
-        raise TypeError("compiler_spec must be string or spack.spec.Compiler")
+def supported(compiler_spec):
+    """Test if a particular compiler is supported."""
+    if not isinstance(compiler_spec, spack.spec.Compiler):
+        compiler_spec = spack.spec.Compiler(compiler_spec)
+    return compiler_spec.name in supported_compilers()
 
 
 @memoized
diff --git a/lib/spack/spack/concretize.py b/lib/spack/spack/concretize.py
index fc360d59ba..8679d3e13e 100644
--- a/lib/spack/spack/concretize.py
+++ b/lib/spack/spack/concretize.py
@@ -89,15 +89,11 @@ class DefaultConcretizer(object):
 
 
     def concretize_compiler(self, spec):
-        """Currently just sets the compiler to gcc or throws an exception
-           if the compiler is set to something else.
-
-           TODO: implement below description.
-
-           If the spec already has a compiler, we're done.  If not, then
-           take the compiler used for the nearest ancestor with a concrete
-           compiler, or use the system default if there is no ancestor
-           with a compiler.
+        """If the spec already has a compiler, we're done.  If not, then take
+           the compiler used for the nearest ancestor with a compiler
+           spec and use that.  If the ancestor's compiler is not
+           concrete, then give it a valid version.  If there is no
+           ancestor with a compiler, use the system default compiler.
 
            Intuition: Use the system default if no package that depends on
            this one has a strict compiler requirement.  Otherwise, try to
@@ -105,10 +101,22 @@ class DefaultConcretizer(object):
            link to this one, to maximize compatibility.
         """
         if spec.compiler and spec.compiler.concrete:
-            if spec.compiler != spack.compilers.default_compiler():
-                raise spack.spec.UnknownCompilerError(str(spec.compiler))
-        else:
-            spec.compiler = spack.compilers.default_compiler()
+            return
+
+        try:
+            nearest = next(p for p in spec.preorder_traversal(direction='parents')
+                           if p.compiler is not None).compiler
+
+            if not nearest.concrete:
+                matches = [c for c in spack.compilers.available_compilers()
+                           if c.name == nearest.name]
+                nearest.versions = sorted(matches)[-1].versions.copy()
+                assert(nearest.concrete)
+
+            spec.compiler = nearest.copy()
+
+        except StopIteration:
+            spec.compiler = spack.compilers.default_compiler().copy()
 
 
     def choose_provider(self, spec, providers):
diff --git a/lib/spack/spack/spec.py b/lib/spack/spack/spec.py
index bb8965ccc8..d0b08cca00 100644
--- a/lib/spack/spack/spec.py
+++ b/lib/spack/spack/spec.py
@@ -196,12 +196,20 @@ class Compiler(object):
         self.versions.add(version)
 
 
+    def _autospec(self, compiler_spec_like):
+        if not isinstance(compiler_spec_like, Compiler):
+            return Compiler(compiler_spec_like)
+        return compiler_spec_like
+
+
     def satisfies(self, other):
+        other = self._autospec(other)
         return (self.name == other.name and
                 self.versions.overlaps(other.versions))
 
 
     def constrain(self, other):
+        other = self._autospec(other)
         if not self.satisfies(other):
             raise UnsatisfiableCompilerSpecError(self, other)
 
@@ -374,14 +382,14 @@ class Spec(object):
         """
         if not self.dependents:
             return self
-        else:
-            # If the spec has multiple dependents, ensure that they all
-            # lead to the same place.  Spack shouldn't deal with any DAGs
-            # with multiple roots, so something's wrong if we find one.
-            depiter = iter(self.dependents.values())
-            first_root = next(depiter).root
-            assert(all(first_root is d.root for d in depiter))
-            return first_root
+
+        # If the spec has multiple dependents, ensure that they all
+        # lead to the same place.  Spack shouldn't deal with any DAGs
+        # with multiple roots, so something's wrong if we find one.
+        depiter = iter(self.dependents.values())
+        first_root = next(depiter).root
+        assert(all(first_root is d.root for d in depiter))
+        return first_root
 
 
     @property
@@ -441,17 +449,28 @@ class Spec(object):
 
            root     [=True]
                If false, this won't yield the root node, just its descendents.
+
+           direction [=children|parents]
+               If 'children', does a traversal of this spec's children.  If
+               'parents', traverses upwards in the DAG towards the root.
+
         """
         depth      = kwargs.get('depth', False)
         key_fun    = kwargs.get('key', id)
         yield_root = kwargs.get('root', True)
         cover      = kwargs.get('cover', 'nodes')
+        direction  = kwargs.get('direction', 'children')
 
         cover_values = ('nodes', 'edges', 'paths')
         if cover not in cover_values:
             raise ValueError("Invalid value for cover: %s.  Choices are %s"
                              % (cover, ",".join(cover_values)))
 
+        direction_values = ('children', 'parents')
+        if direction not in direction_values:
+            raise ValueError("Invalid value for direction: %s.  Choices are %s"
+                             % (direction, ",".join(direction_values)))
+
         if visited is None:
             visited = set()
 
@@ -465,9 +484,13 @@ class Spec(object):
         else:
             if yield_root or d > 0: yield result
 
+        successors = self.dependencies
+        if direction == 'parents':
+            successors = self.dependents
+
         visited.add(key)
-        for name in sorted(self.dependencies):
-            child = self.dependencies[name]
+        for name in sorted(successors):
+            child = successors[name]
             for elt in child.preorder_traversal(visited, d+1, **kwargs):
                 yield elt
 
@@ -776,7 +799,7 @@ class Spec(object):
     def validate_names(self):
         """This checks that names of packages and compilers in this spec are real.
            If they're not, it will raise either UnknownPackageError or
-           UnknownCompilerError.
+           UnsupportedCompilerError.
         """
         for spec in self.preorder_traversal():
             # Don't get a package for a virtual name.
@@ -786,7 +809,7 @@ class Spec(object):
             # validate compiler in addition to the package name.
             if spec.compiler:
                 if not spack.compilers.supported(spec.compiler):
-                    raise UnknownCompilerError(spec.compiler)
+                    raise UnsupportedCompilerError(spec.compiler.name)
 
 
     def constrain(self, other, **kwargs):
@@ -1385,11 +1408,11 @@ class DuplicateCompilerError(SpecError):
         super(DuplicateCompilerError, self).__init__(message)
 
 
-class UnknownCompilerError(SpecError):
+class UnsupportedCompilerError(SpecError):
     """Raised when the user asks for a compiler spack doesn't know about."""
     def __init__(self, compiler_name):
-        super(UnknownCompilerError, self).__init__(
-            "Unknown compiler: %s" % compiler_name)
+        super(UnsupportedCompilerError, self).__init__(
+            "The '%s' compiler is not yet supported." % compiler_name)
 
 
 class DuplicateArchitectureError(SpecError):
diff --git a/lib/spack/spack/test/concretize.py b/lib/spack/spack/test/concretize.py
index 62e2732749..2a989f6766 100644
--- a/lib/spack/spack/test/concretize.py
+++ b/lib/spack/spack/test/concretize.py
@@ -25,7 +25,7 @@
 import unittest
 
 import spack
-from spack.spec import Spec
+from spack.spec import Spec, Compiler
 from spack.test.mock_packages_test import *
 
 class ConcretizeTest(MockPackagesTest):
@@ -163,3 +163,15 @@ class ConcretizeTest(MockPackagesTest):
         spec = Spec('indirect_mpich')
         spec.normalize()
         spec.concretize()
+
+
+    def test_compiler_inheritance(self):
+        spec = Spec('mpileaks')
+        spec.normalize()
+
+        spec['dyninst'].compiler = Compiler('clang')
+        spec.concretize()
+
+        # TODO: not exactly the syntax I would like.
+        self.assertTrue(spec['libdwarf'].compiler.satisfies('clang'))
+        self.assertTrue(spec['libelf'].compiler.satisfies('clang'))