Merge "rust: Add an option to disable LTO for Rust" into main (9b2422d8) · Commits · e / os / android_build_soong

rust/builder.go

+14 −4

Original line number	Diff line number	Diff line
		@@ -158,7 +158,9 @@ func getTransformProperties(ctx ModuleContext, crateType string) transformProper

		func TransformSrcToBinary(ctx ModuleContext, mainSrc android.Path, deps PathDeps, flags Flags,
		outputFile android.WritablePath) buildOutput {
		if ctx.RustModule().compiler.Thinlto() {
		flags.GlobalRustFlags = append(flags.GlobalRustFlags, "-C lto=thin")
		}

		return transformSrctoCrate(ctx, mainSrc, deps, flags, outputFile, getTransformProperties(ctx, "bin"))
		}
		@@ -212,20 +214,28 @@ func TransformRlibstoStaticlib(ctx android.ModuleContext, mainSrc android.Path,

		func TransformSrctoDylib(ctx ModuleContext, mainSrc android.Path, deps PathDeps, flags Flags,
		outputFile android.WritablePath) buildOutput {
		if ctx.RustModule().compiler.Thinlto() {
		flags.GlobalRustFlags = append(flags.GlobalRustFlags, "-C lto=thin")
		}

		return transformSrctoCrate(ctx, mainSrc, deps, flags, outputFile, getTransformProperties(ctx, "dylib"))
		}

		func TransformSrctoStatic(ctx ModuleContext, mainSrc android.Path, deps PathDeps, flags Flags,
		outputFile android.WritablePath) buildOutput {
		if ctx.RustModule().compiler.Thinlto() {
		flags.GlobalRustFlags = append(flags.GlobalRustFlags, "-C lto=thin")
		}

		return transformSrctoCrate(ctx, mainSrc, deps, flags, outputFile, getTransformProperties(ctx, "staticlib"))
		}

		func TransformSrctoShared(ctx ModuleContext, mainSrc android.Path, deps PathDeps, flags Flags,
		outputFile android.WritablePath) buildOutput {
		if ctx.RustModule().compiler.Thinlto() {
		flags.GlobalRustFlags = append(flags.GlobalRustFlags, "-C lto=thin")
		}

		return transformSrctoCrate(ctx, mainSrc, deps, flags, outputFile, getTransformProperties(ctx, "cdylib"))
		}

rust/compiler.go

+15 −0

Original line number	Diff line number	Diff line
		@@ -47,6 +47,7 @@ type compiler interface {
		edition() string
		features() []string
		rustdoc(ctx ModuleContext, flags Flags, deps PathDeps) android.OptionalPath
		Thinlto() bool

		// Output directory in which source-generated code from dependencies is
		// copied. This is equivalent to Cargo's OUT_DIR variable.
		@@ -231,6 +232,15 @@ type BaseCompilerProperties struct {

		// If cargo_env_compat is true, sets the CARGO_PKG_VERSION env var to this value.
		Cargo_pkg_version *string

		// Control whether LTO is used for the final (Rust) linkage. This does not impact
		// cross-language LTO.
		Lto struct {
		// Whether thin LTO should be enabled. By default this is true.
		// LTO provides such a large code size benefit for Rust, this should always
		// be enabled for production builds unless there's a clear need to disable it.
		Thin *bool `android:"arch_variant"`
		} `android:"arch_variant"`
		}

		type baseCompiler struct {
		@@ -273,6 +283,11 @@ func (compiler *baseCompiler) Disabled() bool {
		return false
		}

		// Thin LTO is enabled by default.
		func (compiler *baseCompiler) Thinlto() bool {
		return BoolDefault(compiler.Properties.Lto.Thin, true)
		}

		func (compiler *baseCompiler) SetDisabled() {
		panic("baseCompiler does not implement SetDisabled()")
		}

rust/compiler_test.go

+29 −0

Original line number	Diff line number	Diff line
		@@ -63,6 +63,35 @@ func TestCfgsToFlags(t *testing.T) {
		}
		}

		func TestLtoFlag(t *testing.T) {
		ctx := testRust(t, `
		rust_library_host {
		name: "libfoo",
		srcs: ["foo.rs"],
		crate_name: "foo",
		lto: {
		thin: false,
		}
		}

		rust_library_host {
		name: "libfoo_lto",
		srcs: ["foo.rs"],
		crate_name: "foo",
		}
		`)

		libfoo := ctx.ModuleForTests("libfoo", "linux_glibc_x86_64_dylib").Rule("rustc")
		libfooLto := ctx.ModuleForTests("libfoo_lto", "linux_glibc_x86_64_dylib").Rule("rustc")

		if strings.Contains(libfoo.Args["rustcFlags"], "-C lto=thin") {
		t.Fatalf("libfoo expected to disable lto -- rustcFlags: %#v", libfoo.Args["rustcFlags"])
		}
		if !strings.Contains(libfooLto.Args["rustcFlags"], "-C lto=thin") {
		t.Fatalf("libfoo expected to enable lto by default -- rustcFlags: %#v", libfooLto.Args["rustcFlags"])
		}
		}

		// Test that we reject multiple source files.
		func TestEnforceSingleSourceFile(t *testing.T) {