Fix build error on Android (#588)

Author: taiki-e

.github/workflows/build.yml

@@ -64,6 +64,7 @@ jobs:
     strategy:
       matrix:
         target: [
+          aarch64-linux-android,
           x86_64-unknown-fuchsia,
           x86_64-unknown-redox,
           x86_64-fortanix-unknown-sgx,

.github/workflows/tests.yml

@@ -55,12 +55,15 @@ jobs:
       - run: cargo test --target=${{ matrix.target }} --features=std
       - env:
           RUSTFLAGS: -Dwarnings --cfg getrandom_backend="linux_getrandom"
+          RUSTDOCFLAGS: -Dwarnings --cfg getrandom_backend="linux_getrandom"
         run: cargo test --target=${{ matrix.target }} --features=std
       - env:
           RUSTFLAGS: -Dwarnings --cfg getrandom_test_linux_fallback
+          RUSTDOCFLAGS: -Dwarnings --cfg getrandom_test_linux_fallback
         run: cargo test --features=std
       - env:
           RUSTFLAGS: -Dwarnings --cfg getrandom_backend="rdrand"
+          RUSTDOCFLAGS: -Dwarnings --cfg getrandom_backend="rdrand"
         run: cargo test --features=std
 
   ios:

Cargo.toml

@@ -31,7 +31,7 @@ compiler_builtins = { version = "0.1", optional = true }
 core = { version = "1.0", optional = true, package = "rustc-std-workspace-core" }
 
 # linux_android / linux_android_with_fallback
-[target.'cfg(all(any(target_os = "linux", target_os = "android"), not(any(target_env = "", getrandom_backend = "custom"))))'.dependencies]
+[target.'cfg(all(any(target_os = "linux", target_os = "android"), not(any(getrandom_backend = "custom", getrandom_backend = "rdrand", getrandom_backend = "rndr"))))'.dependencies]
 libc = { version = "0.2.154", default-features = false }
 
 # apple-other