Enable the IL verifier by default.

Change the default value for the "enable_verifier" setting so the
verifier runs unless it is explicitly disabled.

Most projects using Cretonne are best off running the verifier always
until they start caring about compile time performance. Then they can
easily disable the verifier.

cranelift/src/compile.rs

@@ -12,13 +12,9 @@ use utils::{pretty_error, read_to_string, parse_sets_and_isa};
 pub fn run(
     files: Vec<String>,
     flag_print: bool,
-    mut flag_set: Vec<String>,
+    flag_set: Vec<String>,
     flag_isa: String,
 ) -> Result<(), String> {
-    // Enable the verifier by default, since we're reading IL in from a
-    // text file.
-    flag_set.insert(0, "enable_verifier=1".to_string());
-
     let parsed = parse_sets_and_isa(flag_set, flag_isa)?;
 
     for filename in files {