diff --git a/android/makevars.go b/android/makevars.go
index 374986e..3ca7792 100644
--- a/android/makevars.go
+++ b/android/makevars.go
@@ -128,7 +128,7 @@
 type MakeVarsProvider func(ctx MakeVarsContext)
 
 func RegisterMakeVarsProvider(pctx PackageContext, provider MakeVarsProvider) {
-	makeVarsProviders = append(makeVarsProviders, makeVarsProvider{pctx, provider})
+	makeVarsInitProviders = append(makeVarsInitProviders, makeVarsProvider{pctx, provider})
 }
 
 // SingletonMakeVarsProvider is a Singleton with an extra method to provide extra values to be exported to Make.
@@ -142,7 +142,8 @@
 // registerSingletonMakeVarsProvider adds a singleton that implements SingletonMakeVarsProvider to the list of
 // MakeVarsProviders to run.
 func registerSingletonMakeVarsProvider(singleton SingletonMakeVarsProvider) {
-	makeVarsProviders = append(makeVarsProviders, makeVarsProvider{pctx, SingletonmakeVarsProviderAdapter(singleton)})
+	singletonMakeVarsProviders = append(singletonMakeVarsProviders,
+		makeVarsProvider{pctx, SingletonmakeVarsProviderAdapter(singleton)})
 }
 
 // SingletonmakeVarsProviderAdapter converts a SingletonMakeVarsProvider to a MakeVarsProvider.
@@ -171,7 +172,11 @@
 	call MakeVarsProvider
 }
 
-var makeVarsProviders []makeVarsProvider
+// Collection of makevars providers that are registered in init() methods.
+var makeVarsInitProviders []makeVarsProvider
+
+// Collection of singleton makevars providers that are not registered as part of init() methods.
+var singletonMakeVarsProviders []makeVarsProvider
 
 type makeVarsContext struct {
 	SingletonContext
@@ -219,7 +224,7 @@
 	var vars []makeVarsVariable
 	var dists []dist
 	var phonies []phony
-	for _, provider := range makeVarsProviders {
+	for _, provider := range append(makeVarsInitProviders) {
 		mctx := &makeVarsContext{
 			SingletonContext: ctx,
 			pctx:             provider.pctx,
@@ -232,6 +237,25 @@
 		dists = append(dists, mctx.dists...)
 	}
 
+	for _, provider := range append(singletonMakeVarsProviders) {
+		mctx := &makeVarsContext{
+			SingletonContext: ctx,
+			pctx:             provider.pctx,
+		}
+
+		provider.call(mctx)
+
+		vars = append(vars, mctx.vars...)
+		phonies = append(phonies, mctx.phonies...)
+		dists = append(dists, mctx.dists...)
+	}
+
+	// Clear singleton makevars providers after use. Since these are in-memory
+	// singletons, this ensures state is reset if the build tree is processed
+	// multiple times.
+	// TODO(cparsons): Clean up makeVarsProviders to be part of the context.
+	singletonMakeVarsProviders = nil
+
 	ctx.VisitAllModules(func(m Module) {
 		if provider, ok := m.(ModuleMakeVarsProvider); ok && m.Enabled() {
 			mctx := &makeVarsContext{