Provide 32-bit and 64-bit Rust libs by default.

CC libraries which depend on Rust libraries get missing dependency
errors when building 32-bit variants dependent on Rust modules which
don't explicitly have "multilib: both" declared.

Because CC libraries use MultilibBoth by default, Rust should do the
same.

This also fixes a bug where the ARM32 toolchain incorrectly embedded
toolchain64Bit instead of toolchain32Bit.

Bug: 154730212
Test: Rust libraries provide both variants by default.
Change-Id: Ia545fe069d3c6b77c3d18f4f10267e2c72ee0bab

1 files changed, 14 insertions, 1 deletions

diff --git a/rust/rust_test.go b/rust/rust_test.go
index 02b190f0f..32eddc161 100644
--- a/rust/rust_test.go
+++ b/rust/rust_test.go
@@ -240,7 +240,7 @@ func TestNoStdlibs(t *testing.T) {
 		rust_binary {
 			name: "fizz-buzz",
 			srcs: ["foo.rs"],
-                        no_stdlibs: true,
+			no_stdlibs: true,
 		}`)
 	module := ctx.ModuleForTests("fizz-buzz", "android_arm64_armv8-a").Module().(*Module)
 
@@ -248,3 +248,16 @@ func TestNoStdlibs(t *testing.T) {
 		t.Errorf("no_stdlibs did not suppress dependency on libstd")
 	}
 }
+
+// Test that libraries provide both 32-bit and 64-bit variants.
+func TestMultilib(t *testing.T) {
+	ctx := testRust(t, `
+		rust_library_rlib {
+			name: "libfoo",
+			srcs: ["foo.rs"],
+			crate_name: "foo",
+		}`)
+
+	_ = ctx.ModuleForTests("libfoo", "android_arm64_armv8-a_rlib")
+	_ = ctx.ModuleForTests("libfoo", "android_arm_armv7-a-neon_rlib")
+}