diff --git a/cc/cc_test.go b/cc/cc_test.go
index e2dba90..cc52547 100644
--- a/cc/cc_test.go
+++ b/cc/cc_test.go
@@ -40,6 +40,7 @@
 var prepareForCcTest = android.GroupFixturePreparers(
 	PrepareForTestWithCcIncludeVndk,
 	android.FixtureModifyProductVariables(func(variables android.FixtureProductVariables) {
+		variables.VendorApiLevel = StringPtr("202404")
 		variables.DeviceVndkVersion = StringPtr("current")
 		variables.Platform_vndk_version = StringPtr("29")
 	}),
@@ -2131,11 +2132,13 @@
 	ensureStringContains(t, vendor_cflags, "-D__ANDROID_VNDK__")
 	ensureStringContains(t, vendor_cflags, "-D__ANDROID_VENDOR__")
 	ensureStringNotContains(t, vendor_cflags, "-D__ANDROID_PRODUCT__")
+	ensureStringContains(t, vendor_cflags, "-D__ANDROID_VENDOR_API__=202404")
 
 	product_cflags := product_static.Rule("cc").Args["cFlags"]
 	ensureStringContains(t, product_cflags, "-D__ANDROID_VNDK__")
 	ensureStringContains(t, product_cflags, "-D__ANDROID_PRODUCT__")
 	ensureStringNotContains(t, product_cflags, "-D__ANDROID_VENDOR__")
+	ensureStringNotContains(t, product_cflags, "-D__ANDROID_VENDOR_API__=202404")
 }
 
 func TestEnforceProductVndkVersionErrors(t *testing.T) {
diff --git a/cc/compiler.go b/cc/compiler.go
index 490d3cc..bb7885b 100644
--- a/cc/compiler.go
+++ b/cc/compiler.go
@@ -406,6 +406,15 @@
 		flags.Global.CommonFlags = append(flags.Global.CommonFlags, "-D__ANDROID_VNDK__")
 		if ctx.inVendor() {
 			flags.Global.CommonFlags = append(flags.Global.CommonFlags, "-D__ANDROID_VENDOR__")
+
+			vendorApiLevel := ctx.Config().VendorApiLevel()
+			if vendorApiLevel == "" {
+				// TODO(b/314036847): This is a fallback for UDC targets.
+				// This must be a build failure when UDC is no longer built
+				// from this source tree.
+				vendorApiLevel = ctx.Config().PlatformSdkVersion().String()
+			}
+			flags.Global.CommonFlags = append(flags.Global.CommonFlags, "-D__ANDROID_VENDOR_API__="+vendorApiLevel)
 		} else if ctx.inProduct() {
 			flags.Global.CommonFlags = append(flags.Global.CommonFlags, "-D__ANDROID_PRODUCT__")
 		}