improve error handling

libcsp-cargo-build/Cargo.toml

@@ -12,3 +12,4 @@ categories = ["aerospace", "external-ffi-bindings", "no-std", "hardware-support"
 
 [dependencies]
 cc = "1"
+thiserror = "1"

libcsp-cargo-build/src/lib.rs

@@ -133,9 +133,11 @@ pub struct Builder {
     build: cc::Build,
 }
 
-#[derive(Debug, Copy, Clone, PartialEq, Eq)]
+#[derive(Debug, Copy, Clone, PartialEq, Eq, thiserror::Error)]
 pub enum BuildCreationError {
+    #[error("The specified libcsp path does not exist")]
     PathDoesNotExist,
+    #[error("The specified libcsp path does not have the expected format of the library")]
     InvalidLibcspFormat,
 }