Stricter compatibility rules for OS and compiler when reusing specs (#31170)

* Stricter compatibility rules for OS and compiler when reusing specs
* Add unit test

lib/spack/spack/solver/asp.py

@@ -631,6 +631,7 @@ def visit(node):
 
         # Load the file itself
         self.control.load(os.path.join(parent_dir, 'concretize.lp'))
+        self.control.load(os.path.join(parent_dir, "os_facts.lp"))
         self.control.load(os.path.join(parent_dir, "display.lp"))
         timer.phase("load")
 

lib/spack/spack/solver/concretize.lp

@@ -737,9 +737,14 @@ node_os_mismatch(Package, Dependency) :-
 % every OS is compatible with itself. We can use `os_compatible` to declare
 os_compatible(OS, OS) :- os(OS).
 
-% OS compatibility rules for reusing solves.
-% catalina binaries can be used on bigsur. Direction is package -> dependency.
-os_compatible("bigsur", "catalina").
+% Transitive compatibility among operating systems
+os_compatible(OS1, OS3) :- os_compatible(OS1, OS2), os_compatible(OS2, OS3).
+
+% We can select only operating systems compatible with the ones
+% for which we can build software. We need a cardinality constraint
+% since we might have more than one "buildable_os(OS)" fact.
+:- not 1 { os_compatible(CurrentOS, ReusedOS) : buildable_os(CurrentOS) },
+   node_os(Package, ReusedOS).
 
 % If an OS is set explicitly respect the value
 node_os(Package, OS) :- node_os_set(Package, OS), node(Package).
@@ -961,6 +966,9 @@ compiler_weight(Package, 100)
     not node_compiler_preference(Package, Compiler, Version, _),
     not default_compiler_preference(Compiler, Version, _).
 
+% For the time being, be strict and reuse only if the compiler match one we have on the system
+:- node_compiler_version(Package, Compiler, Version), not compiler_version(Compiler, Version).
+
 #defined node_compiler_preference/4.
 #defined default_compiler_preference/3.
 
@@ -1269,6 +1277,7 @@ opt_criterion(1, "non-preferred targets").
 #heuristic variant_value(Package, Variant, Value) : variant_default_value(Package, Variant, Value), node(Package). [10, true]
 #heuristic provider(Package, Virtual) : possible_provider_weight(Package, Virtual, 0, _), virtual_node(Virtual). [10, true]
 #heuristic node(Package) : possible_provider_weight(Package, Virtual, 0, _), virtual_node(Virtual). [10, true]
+#heuristic node_os(Package, OS) : buildable_os(OS). [10, true]
 
 %-----------
 % Notes

lib/spack/spack/solver/os_facts.lp

@@ -0,0 +1,22 @@
+% Copyright 2013-2022 Lawrence Livermore National Security, LLC and other
+% Spack Project Developers. See the top-level COPYRIGHT file for details.
+%
+% SPDX-License-Identifier: (Apache-2.0 OR MIT)
+
+% OS compatibility rules for reusing solves.
+% os_compatible(RecentOS, OlderOS)
+% OlderOS binaries can be used on RecentOS
+
+% macOS
+os_compatible("monterey", "bigsur").
+os_compatible("bigsur", "catalina").
+
+% Ubuntu
+os_compatible("ubuntu22.04", "ubuntu21.10").
+os_compatible("ubuntu21.10", "ubuntu21.04").
+os_compatible("ubuntu21.04", "ubuntu20.10").
+os_compatible("ubuntu20.10", "ubuntu20.04").
+os_compatible("ubuntu20.04", "ubuntu19.10").
+os_compatible("ubuntu19.10", "ubuntu19.04").
+os_compatible("ubuntu19.04", "ubuntu18.10").
+os_compatible("ubuntu18.10", "ubuntu18.04").

lib/spack/spack/test/concretize.py

@@ -1786,3 +1786,25 @@ def test_version_weight_and_provenance(self):
             ]:
                 assert criterion in result.criteria
             assert result.specs[0].satisfies('^b@1.0')
+
+    @pytest.mark.regression('31169')
+    def test_not_reusing_incompatible_os_or_compiler(self):
+        import spack.solver.asp
+        if spack.config.get('config:concretizer') == 'original':
+            pytest.skip('Original concretizer cannot reuse')
+
+        root_spec = spack.spec.Spec('b')
+        s = root_spec.concretized()
+        wrong_compiler, wrong_os = s.copy(), s.copy()
+        wrong_compiler.compiler = spack.spec.CompilerSpec('gcc@12.1.0')
+        wrong_os.architecture = spack.spec.ArchSpec('test-ubuntu2204-x86_64')
+        reusable_specs = [wrong_compiler, wrong_os]
+        with spack.config.override("concretizer:reuse", True):
+            solver = spack.solver.asp.Solver()
+            setup = spack.solver.asp.SpackSolverSetup()
+            result = solver.driver.solve(
+                setup, [root_spec], reuse=reusable_specs, out=sys.stdout
+            )
+        concrete_spec = result.specs[0]
+        assert concrete_spec.satisfies('%gcc@4.5.0')
+        assert concrete_spec.satisfies('os=debian6')