assembler refactor

src/main.rs

@@ -96,27 +96,18 @@ fn output_path(
 fn assemble(options: &CliOptions, file: &Path, asm_file: OutFile) -> Result<OutFile, WreccError> {
     let output_path = output_path(file, &options.output_path, options.no_link, "o");
 
-    let output = match std::env::consts::OS {
-        "linux" => {
-            Command::new("as")
-            .arg(asm_file.get())
-            .arg("-o")
-            .arg(output_path.get())
-            .output()
-            .map_err(|_| WreccError::Sys("could not invoke assembler 'as'".to_string()))?
-        }
-        "macos" => {
-            Command::new("as")
-            .arg(asm_file.get())
-            .arg("-o")
-            .arg(output_path.get())
-            .arg("-arch")
-            .arg("x86_64")
-            .output()
-            .map_err(|_| WreccError::Sys("could not invoke assembler 'as'".to_string()))?
-        }
-        _ => return Err(WreccError::Sys(String::from("only supports linux and macos"))),
-    };
+    let mut cmd = Command::new("as");
+    cmd.arg(asm_file.get()).arg("-o").arg(output_path.get());
+
+    // Specify target architecture for macos
+    // so that apple silicon chips can run x86-64 binary through rosetta
+    if std::env::consts::OS == "macos" {
+        cmd.arg("-arch").arg("x86_64");
+    }
+
+    let output = cmd
+        .output()
+        .map_err(|_| WreccError::Sys("could not invoke assembler 'as'".to_string()))?;
 
     if output.status.success() {
         Ok(output_path)

wrecc_compiler/src/compiler/scanner.rs

@@ -353,10 +353,12 @@ impl<'a> Scanner<'a> {
                 .ok_or(Error::new(pp_token, ErrorKind::Eof("expected character literal")))?;
             self.escape_char(char_to_escape, char_iter)
                 .ok_or(Error::new(pp_token, ErrorKind::InvalidEscape(char_string)))
-        // strings can contain non-ascii chars
         } else if c.is_ascii() || is_string {
+            // strings can contain non-ascii chars
             Ok(c)
         } else {
+            // doesn't apply to escaped chars since they can are in
+            // range [0;255] which is valid while valid ascii is only [0;127]
             Err(Error::new(pp_token, ErrorKind::CharLiteralAscii(c)))
         }
     }