diff --git a/android/androidmk.go b/android/androidmk.go
index fd74507..2732c82 100644
--- a/android/androidmk.go
+++ b/android/androidmk.go
@@ -33,7 +33,7 @@
 }
 
 type AndroidMkDataProvider interface {
-	AndroidMk() (AndroidMkData, error)
+	AndroidMk() AndroidMkData
 	BaseModuleName() string
 }
 
diff --git a/cc/androidmk.go b/cc/androidmk.go
index 561a0a3..4421b1c 100644
--- a/cc/androidmk.go
+++ b/cc/androidmk.go
@@ -49,29 +49,34 @@
 	}
 }
 
-func (c *Module) AndroidMk() (ret android.AndroidMkData, err error) {
+func (c *Module) AndroidMk() android.AndroidMkData {
 	if c.Properties.HideFromMake {
-		ret.Disabled = true
-		return ret, nil
+		return android.AndroidMkData{
+			Disabled: true,
+		}
 	}
 
-	ret.OutputFile = c.outputFile
-	ret.Extra = append(ret.Extra, func(w io.Writer, outputFile android.Path) {
-		fmt.Fprintln(w, "LOCAL_SANITIZE := never")
-		if len(c.Properties.AndroidMkSharedLibs) > 0 {
-			fmt.Fprintln(w, "LOCAL_SHARED_LIBRARIES := "+strings.Join(c.Properties.AndroidMkSharedLibs, " "))
-		}
-		if c.Target().Os == android.Android && c.Properties.Sdk_version != "" && !c.vndk() {
-			fmt.Fprintln(w, "LOCAL_SDK_VERSION := "+c.Properties.Sdk_version)
-			fmt.Fprintln(w, "LOCAL_NDK_STL_VARIANT := none")
-		} else {
-			// These are already included in LOCAL_SHARED_LIBRARIES
-			fmt.Fprintln(w, "LOCAL_CXX_STL := none")
-		}
-		if c.vndk() {
-			fmt.Fprintln(w, "LOCAL_USE_VNDK := true")
-		}
-	})
+	ret := android.AndroidMkData{
+		OutputFile: c.outputFile,
+		Extra: []android.AndroidMkExtraFunc{
+			func(w io.Writer, outputFile android.Path) {
+				fmt.Fprintln(w, "LOCAL_SANITIZE := never")
+				if len(c.Properties.AndroidMkSharedLibs) > 0 {
+					fmt.Fprintln(w, "LOCAL_SHARED_LIBRARIES := "+strings.Join(c.Properties.AndroidMkSharedLibs, " "))
+				}
+				if c.Target().Os == android.Android && c.Properties.Sdk_version != "" && !c.vndk() {
+					fmt.Fprintln(w, "LOCAL_SDK_VERSION := "+c.Properties.Sdk_version)
+					fmt.Fprintln(w, "LOCAL_NDK_STL_VARIANT := none")
+				} else {
+					// These are already included in LOCAL_SHARED_LIBRARIES
+					fmt.Fprintln(w, "LOCAL_CXX_STL := none")
+				}
+				if c.vndk() {
+					fmt.Fprintln(w, "LOCAL_USE_VNDK := true")
+				}
+			},
+		},
+	}
 
 	for _, feature := range c.features {
 		c.subAndroidMk(&ret, feature)
@@ -90,7 +95,7 @@
 		ret.SubName += vendorSuffix
 	}
 
-	return ret, nil
+	return ret
 }
 
 func androidMkWriteTestData(data android.Paths, ctx AndroidMkContext, ret *android.AndroidMkData) {
diff --git a/java/androidmk.go b/java/androidmk.go
index fd967cb..1939924 100644
--- a/java/androidmk.go
+++ b/java/androidmk.go
@@ -21,20 +21,26 @@
 	"android/soong/android"
 )
 
-func (library *Library) AndroidMk() (ret android.AndroidMkData, err error) {
-	ret.Class = "JAVA_LIBRARIES"
-	ret.OutputFile = android.OptionalPathForPath(library.outputFile)
-	ret.Extra = append(ret.Extra, func(w io.Writer, outputFile android.Path) {
-		fmt.Fprintln(w, "LOCAL_MODULE_SUFFIX := .jar")
-	})
-	return
+func (library *Library) AndroidMk() android.AndroidMkData {
+	return android.AndroidMkData{
+		Class:      "JAVA_LIBRARIES",
+		OutputFile: android.OptionalPathForPath(library.outputFile),
+		Extra: []android.AndroidMkExtraFunc{
+			func(w io.Writer, outputFile android.Path) {
+				fmt.Fprintln(w, "LOCAL_MODULE_SUFFIX := .jar")
+			},
+		},
+	}
 }
 
-func (prebuilt *Import) AndroidMk() (ret android.AndroidMkData, err error) {
-	ret.Class = "JAVA_LIBRARIES"
-	ret.OutputFile = android.OptionalPathForPath(prebuilt.combinedClasspathFile)
-	ret.Extra = append(ret.Extra, func(w io.Writer, outputFile android.Path) {
-		fmt.Fprintln(w, "LOCAL_MODULE_SUFFIX := .jar")
-	})
-	return
+func (prebuilt *Import) AndroidMk() android.AndroidMkData {
+	return android.AndroidMkData{
+		Class:      "JAVA_LIBRARIES",
+		OutputFile: android.OptionalPathForPath(prebuilt.combinedClasspathFile),
+		Extra: []android.AndroidMkExtraFunc{
+			func(w io.Writer, outputFile android.Path) {
+				fmt.Fprintln(w, "LOCAL_MODULE_SUFFIX := .jar")
+			},
+		},
+	}
 }
diff --git a/phony/phony.go b/phony/phony.go
index 053ed56..5f0187f 100644
--- a/phony/phony.go
+++ b/phony/phony.go
@@ -48,13 +48,14 @@
 	}
 }
 
-func (p *phony) AndroidMk() (ret android.AndroidMkData, err error) {
-	ret.Custom = func(w io.Writer, name, prefix, moduleDir string) {
-		fmt.Fprintln(w, "\ninclude $(CLEAR_VARS)")
-		fmt.Fprintln(w, "LOCAL_PATH :=", moduleDir)
-		fmt.Fprintln(w, "LOCAL_MODULE :=", name)
-		fmt.Fprintln(w, "LOCAL_REQUIRED_MODULES := "+strings.Join(p.requiredModuleNames, " "))
-		fmt.Fprintln(w, "include $(BUILD_PHONY_PACKAGE)")
+func (p *phony) AndroidMk() android.AndroidMkData {
+	return android.AndroidMkData{
+		Custom: func(w io.Writer, name, prefix, moduleDir string) {
+			fmt.Fprintln(w, "\ninclude $(CLEAR_VARS)")
+			fmt.Fprintln(w, "LOCAL_PATH :=", moduleDir)
+			fmt.Fprintln(w, "LOCAL_MODULE :=", name)
+			fmt.Fprintln(w, "LOCAL_REQUIRED_MODULES := "+strings.Join(p.requiredModuleNames, " "))
+			fmt.Fprintln(w, "include $(BUILD_PHONY_PACKAGE)")
+		},
 	}
-	return
 }
diff --git a/python/androidmk.go b/python/androidmk.go
index 386eeee..ab24e99 100644
--- a/python/androidmk.go
+++ b/python/androidmk.go
@@ -38,10 +38,12 @@
 	}
 }
 
-func (p *pythonBaseModule) AndroidMk() (ret android.AndroidMkData, err error) {
+func (p *pythonBaseModule) AndroidMk() android.AndroidMkData {
+	ret := android.AndroidMkData{}
+
 	p.subAndroidMk(&ret, p.installer)
 
-	return ret, nil
+	return ret
 }
 
 func (p *pythonBinaryHostDecorator) AndroidMk(base *pythonBaseModule, ret *android.AndroidMkData) {