Allow rules and targets to specify extra execution platform constraints.

RuleClass.Builder now allows authors to specify whether a rule's targets
can add additional constraints on the execution platform, and to declare
additional constraints for all targets of that rule.

Targets which support this now have an attribute,
"exec_compatible_with", which supports specifying additional constraints
that the execution platform used must match.

This attribute is non-configurable. It will only affect execution
platforms used during toolchain resolution.

Part of #5217.

Change-Id: Id2400dbf869a00aa2be3e3d2f085c2850cd6dc00

Closes #5227.

Change-Id: If7d55f08f7f44bc7d7f6dfec86a3e6bcd68574b9
PiperOrigin-RevId: 199326255

1 files changed, 5 insertions, 1 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeExecutor.java b/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeExecutor.java
index 906924fa9f..6cf2bd5d77 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeExecutor.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeExecutor.java
@@ -968,7 +968,11 @@ public abstract class SkyframeExecutor implements WalkableGraphFactory {
     SkyFunctionEnvironmentForTesting env =
         new SkyFunctionEnvironmentForTesting(buildDriver, eventHandler, this);
     return ToolchainUtil.createToolchainContext(
-        env, "", requiredToolchains, config == null ? null : BuildConfigurationValue.key(config));
+        env,
+        "",
+        requiredToolchains,
+        /* execConstraintLabels= */ ImmutableSet.of(),
+        config == null ? null : BuildConfigurationValue.key(config));
   }
 
   /**