Add a new crate for testing `no-std`

* This needs to be enabled `.travis.yml` but I won´t dare changing it
becomes this will fail on `stable` compiler
* Run the test by `cargo test -p no-std-tests`

Cargo.toml

@@ -1,2 +1,2 @@
 [workspace]
-members = ["uint", "fixed-hash", "ethereum-types", "tests", "ethbloom"]
+members = ["uint", "fixed-hash", "ethereum-types", "tests", "ethbloom", "no-std-tests"]

no-std-tests/Cargo.toml

@@ -0,0 +1,12 @@
+[package]
+name = "no-std-tests"
+version = "0.0.1"
+authors = ["Parity Technologies <admin@parity.io>"]
+description = "Tests for no-std environments"
+license = "MIT"
+
+[dependencies]
+libc = { version = "0.2", default-features = false }
+ethereum-types = { git = "https://github.com/niklasad1/primitives", default-features = false, branch = "ethereum-types/no-std" }
+ethbloom = { git = "https://github.com/niklasad1/primitives", default-features = false, branch = "ethereum-types/no-std" }
+fixed-hash = { git = "https://github.com/niklasad1/primitives", default-features = false, branch = "ethereum-types/no-std" }

no-std-tests/src/main.rs

@@ -0,0 +1,27 @@
+#![feature(lang_items, start, panic_implementation)]
+#![no_std]
+
+extern crate libc;
+extern crate ethereum_types;
+extern crate ethbloom;
+extern crate fixed_hash;
+
+use ethereum_types::{Address, Public, Secret, Signature};
+
+#[start]
+fn start(_argc: isize, _argv: *const *const u8) -> isize {
+   0
+}
+
+#[cfg(not(test))]
+#[lang = "eh_personality"]
+#[no_mangle]
+pub extern "C" fn rust_eh_personality() {}
+
+#[cfg(not(test))]
+#[panic_implementation]
+fn panic(_info: &core::panic::PanicInfo) -> ! {
+    unsafe {
+        libc::abort();
+    }
+}