internal/rosa: global preset flags

These changes preset behaviour globally. Useful for ad hoc workarounds for development or bootstrapping on resource-constrained systems.

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

internal/rosa/all.go

@@ -322,15 +322,29 @@ var (
 	}
 	// artifactsOnce is for lazy initialisation of artifacts.
 	artifactsOnce [_toolchainEnd][len(artifactsM)]sync.Once
+
+	// presetOpts globally modifies behaviour of presets.
+	presetOpts int
 )
 
+const (
+	// OptSkipCheck skips running all test suites.
+	OptSkipCheck = 1 << iota
+	// OptLLVMNoLTO disables LTO in all [LLVM] stages.
+	OptLLVMNoLTO
+)
+
+// Flags returns the current preset flags
+func Flags() int { return presetOpts }
+
 // zero zeros the value pointed to by p.
 func zero[T any](p *T) { var v T; *p = v }
 
 // DropCaches arranges for all cached [pkg.Artifact] to be freed some time after
 // it returns. Must not be used concurrently with any other function from this
 // package.
-func DropCaches() {
+func DropCaches(flags int) {
+	presetOpts = flags
 	zero(&artifacts)
 	zero(&artifactsOnce)
 }