Compiler uses a default optimization level when unconfigured

compiler/compile-unit.go

@@ -94,11 +94,14 @@ func (this *Compiler) CompileIRModule (module *llvm.Module, filetype string) err
 //   - clang
 // If none were found, it returns an error.
 func (this *Compiler) FindBackend (filetype string) (string, []string, error) {
+	optimization := "0"
+	if this.Optimization != "" { optimization = this.Optimization }
+
 	llcArgs := []string {
 		"-",
 		fmt.Sprintf("-filetype=%s", filetype),
 		"-o", this.Output,
-		fmt.Sprintf("-O=%s", this.Optimization),
+		fmt.Sprintf("-O=%s", optimization),
 	}
 
 	// attempt to use llc command