#487 Add thumbv4t-none-eabi to the list of targets that don't support…

… atomics.

build.rs

@@ -33,7 +33,7 @@ fn target_has_atomic_cas(target: &str) -> bool {
 
 fn target_has_atomics(target: &str) -> bool {
     match &target[..] {
-        "msp430-none-elf" | "riscv32i-unknown-none-elf" | "riscv32imc-unknown-none-elf" => false,
+        "thumbv4t-none-eabi" | "msp430-none-elf" | "riscv32i-unknown-none-elf" | "riscv32imc-unknown-none-elf" => false,
         _ => true,
     }
 }