treewide: document linkname uses

These provide justification for each use of linkname. Poorly thought out uses of linkname are removed.

Signed-off-by: Ophestra <cat@gensokyo.uk>

container/check/absolute_test.go

@@ -14,8 +14,10 @@ import (
 	. "hakurei.app/container/check"
 )
 
+// unsafeAbs returns check.Absolute on any string value.
+//
 //go:linkname unsafeAbs hakurei.app/container/check.unsafeAbs
-func unsafeAbs(_ string) *Absolute
+func unsafeAbs(pathname string) *Absolute
 
 func TestAbsoluteError(t *testing.T) {
 	t.Parallel()

container/fhs/abs.go

@@ -8,8 +8,10 @@ import (
 
 /* constants in this file bypass abs check, be extremely careful when changing them! */
 
+// unsafeAbs returns check.Absolute on any string value.
+//
 //go:linkname unsafeAbs hakurei.app/container/check.unsafeAbs
-func unsafeAbs(_ string) *check.Absolute
+func unsafeAbs(pathname string) *check.Absolute
 
 var (
 	// AbsRoot is [Root] as [check.Absolute].

container/stub/exit_test.go

@@ -7,8 +7,10 @@ import (
 	"hakurei.app/container/stub"
 )
 
+// Made available here to check panic recovery behaviour.
+//
 //go:linkname handleExitNew hakurei.app/container/stub.handleExitNew
-func handleExitNew(_ testing.TB)
+func handleExitNew(t testing.TB)
 
 // overrideTFailNow overrides the Fail and FailNow method.
 type overrideTFailNow struct {