Enable compilers other than gcc

src/app.rs

@@ -274,7 +274,7 @@ fn build(mode: &Option<String>, force_recompile: bool) -> std::io::Result<()> {
         }
     }
 
-    let mut command = Command::new("gcc");
+    let mut command = Command::new(conf.compiler.as_deref().unwrap_or("gcc"));
 
     for arg in &build_config.args {
         command.arg(arg);

src/config.rs

@@ -1,5 +1,7 @@
 #[derive(serde::Deserialize, serde::Serialize, Default)]
 pub struct Config {
+    /// The C compiler to use (defaults to "gcc")
+    pub compiler: Option<String>,
     /// The name of the output binary
     pub name: String,
     /// The default build to use