Add additional info to the error when subrules use toolchains and must enable AEGs
This fixes https://github.com/bazelbuild/bazel/issues/24067.
PiperOrigin-RevId: 689389370
Change-Id: I9fd31e1d5d51f8c2938a9d249177ddcac7cf1a7e
diff --git a/src/main/java/com/google/devtools/build/lib/analysis/starlark/StarlarkSubrule.java b/src/main/java/com/google/devtools/build/lib/analysis/starlark/StarlarkSubrule.java
index 5329cb4..bdaf58c 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/starlark/StarlarkSubrule.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/starlark/StarlarkSubrule.java
@@ -382,7 +382,9 @@
/* resolveToolchainDataFunc= */ ruleContext::getToolchainInfo,
/* resolvedToolchainTypeLabels= */ getAutomaticExecGroupLabels());
} else {
- throw Starlark.errorf("subrules using toolchains must enable automatic exec-groups");
+ throw Starlark.errorf(
+ "subrules using toolchains must enable automatic exec-groups. For more info, see"
+ + " https://bazel.build/extending/auto-exec-groups#migration-aegs");
}
}
diff --git a/src/main/java/com/google/devtools/build/lib/starlarkbuildapi/StarlarkRuleFunctionsApi.java b/src/main/java/com/google/devtools/build/lib/starlarkbuildapi/StarlarkRuleFunctionsApi.java
index eb9f739..d2824b8 100644
--- a/src/main/java/com/google/devtools/build/lib/starlarkbuildapi/StarlarkRuleFunctionsApi.java
+++ b/src/main/java/com/google/devtools/build/lib/starlarkbuildapi/StarlarkRuleFunctionsApi.java
@@ -988,7 +988,10 @@
"If set, the set of toolchains this subrule requires. The list can contain String,"
+ " Label, or StarlarkToolchainTypeApi objects, in any combination. Toolchains"
+ " will be found by checking the current platform, and provided to the subrule"
- + " implementation via <code>ctx.toolchains</code>."),
+ + " implementation via <code>ctx.toolchains</code>. Note that AEGs need to be"
+ + " enabled on the consuming rule(s) if this parameter is set. In case you"
+ + " haven't migrated to AEGs yet, see"
+ + " https://bazel.build/extending/auto-exec-groups#migration-aegs."),
@Param(
name = "fragments",
allowedTypes = {@ParamType(type = Sequence.class, generic1 = String.class)},
