From 5f788403089bf03232ed601c8095119a8bd76d4f Mon Sep 17 00:00:00 2001
From: Chris Wailes <chriswailes@google.com>
Date: Thu, 2 Mar 2023 16:06:01 -0800
Subject: [PATCH] Enable LTO for Rust dylibs

Test: m rust
Test: TH
Change-Id: I2257fe9fce1457821a5cf7df644c73f3137a62bb
---
 rust/builder.go       | 2 ++
 rust/config/global.go | 1 +
 2 files changed, 3 insertions(+)

diff --git a/rust/builder.go b/rust/builder.go
index a2f1238c2..55664512d 100644
--- a/rust/builder.go
+++ b/rust/builder.go
@@ -134,6 +134,8 @@ func TransformSrctoRlib(ctx ModuleContext, mainSrc android.Path, deps PathDeps,
 
 func TransformSrctoDylib(ctx ModuleContext, mainSrc android.Path, deps PathDeps, flags Flags,
 	outputFile android.WritablePath) buildOutput {
+	flags.GlobalRustFlags = append(flags.GlobalRustFlags, "-C lto=thin")
+
 	return transformSrctoCrate(ctx, mainSrc, deps, flags, outputFile, "dylib")
 }
 
diff --git a/rust/config/global.go b/rust/config/global.go
index 0dface47b..937502238 100644
--- a/rust/config/global.go
+++ b/rust/config/global.go
@@ -54,6 +54,7 @@ var (
 		// TODO (b/267698452): Temporary workaround until the "no unstable
 		// features" policy is enforced.
 		"-A stable-features",
+		"-Zdylib-lto",
 	}
 
 	deviceGlobalRustFlags = []string{