rustc: Refactor lint check and avoid a segv fault

The segv fault issue is #1566

Author: lht

src/comp/driver/driver.rs

@@ -203,9 +203,14 @@ fn compile_upto(sess: session, cfg: ast::crate_cfg,
         bind last_use::find_last_uses(crate, def_map, ref_map, ty_cx));
     time(time_passes, "kind checking",
          bind kind::check_crate(ty_cx, method_map, last_uses, crate));
-    if vec::len(sess.opts.lint_opts) > 0u {
-        let timer = bind time(time_passes, _, _);
-        lint::check_crate(ty_cx, crate, sess.opts.lint_opts, timer)
+
+    vec::iter(sess.opts.lint_opts) {|lopt|
+        alt lopt {
+          ctypes {
+            time(time_passes, "ctypes usage checking",
+                 bind lint::check_ctypes(ty_cx, crate))
+          }
+        }
     }
 
     if upto == cu_no_trans { ret {crate: crate, tcx: some(ty_cx), src: src}; }
@@ -384,7 +389,7 @@ fn build_session_options(match: getopts::match,
 
     let parse_only = opt_present(match, "parse-only");
     let no_trans = opt_present(match, "no-trans");
-    let lint_opts : [lint::option] = [];
+    let lint_opts = [];
     if !opt_present(match, "no-lint-ctypes") {
         lint_opts += [lint::ctypes];
     }

src/comp/middle/lint.rs

@@ -8,31 +8,19 @@ enum option {
     ctypes;
 }
 
-fn check_crate(tcx: ty::ctxt, crate: @ast::crate,
-               checks: [option], timer: block(str, fn@())) {
-    let ccx = @{tcx: tcx};
-    vec::iter(checks) {|c|
-        alt c {
-          ctypes {
-            timer("ctypes usage checking", bind check_ctypes(ccx, crate))
-          }
-        }
-    }
-}
-
-fn check_ctypes(ccx: @crate_ctxt, crate: @ast::crate) {
-    fn check_native_fn(ccx: @crate_ctxt, decl: ast::fn_decl) {
+fn check_ctypes(tcx: ty::ctxt, crate: @ast::crate) {
+    fn check_native_fn(tcx: ty::ctxt, decl: ast::fn_decl) {
         let tys = vec::map(decl.inputs) {|a| a.ty };
         for ty in (tys + [decl.output]) {
             alt ty.node {
               ast::ty_int(ast::ty_i) {
-                ccx.tcx.sess.span_warn(
+                tcx.sess.span_warn(
                     ty.span,
                     "found rust type `int` in native module, while \
                      ctypes::c_int or ctypes::long should be used");
               }
               ast::ty_uint(ast::ty_u) {
-                ccx.tcx.sess.span_warn(
+                tcx.sess.span_warn(
                     ty.span,
                     "found rust type `uint` in native module, while \
                      ctypes::c_uint or ctypes::ulong should be used");
@@ -42,13 +30,13 @@ fn check_ctypes(ccx: @crate_ctxt, crate: @ast::crate) {
         }
     }
 
-    fn check_item(ccx: @crate_ctxt, it: @ast::item) {
+    fn check_item(tcx: ty::ctxt, it: @ast::item) {
         alt it.node {
           ast::item_native_mod(nmod) {
             for ni in nmod.items {
                 alt ni.node {
                   ast::native_item_fn(decl, tps) {
-                    check_native_fn(ccx, decl);
+                    check_native_fn(tcx, decl);
                   }
                   _ { }
                 }
@@ -59,7 +47,7 @@ fn check_ctypes(ccx: @crate_ctxt, crate: @ast::crate) {
     }
 
     let visit = visit::mk_simple_visitor(@{
-        visit_item: bind check_item(ccx, _)
+        visit_item: bind check_item(tcx, _)
         with *visit::default_simple_visitor()
     });
     visit::visit_crate(*crate, (), visit);