Add a very basic crate-dump utility

'rustc -ls [cratelib]' will now dump out a list of symbols defined by
the crate, as well as a short description of what they are.

1 files changed, 7 insertions, 2 deletions

diff --git a/src/comp/driver/rustc.rs b/src/comp/driver/rustc.rs
index 36827b73ba0..928c934a7ec 100644
--- a/src/comp/driver/rustc.rs
+++ b/src/comp/driver/rustc.rs
@@ -98,6 +98,7 @@ fn usage(session.session sess, str argv0) {
     log "    -glue              generate glue.bc file";
     log "    -shared            compile a shared-library crate";
     log "    -pp                pretty-print the input instead of compiling";
+    log "    -ls                list the symbols defined by a crate file";
     log "    -L <path>          add a directory to the library search path";
     log "    -h                 display this message";
     log "";
@@ -130,6 +131,7 @@ impure fn main(vec[str] args) {
     let bool do_warn = true;
     let bool shared = false;
     let bool pretty = false;
+    let bool ls = false;
     let bool glue = false;
 
     // FIXME: Maybe we should support -O0, -O1, -Os, etc
@@ -152,6 +154,8 @@ impure fn main(vec[str] args) {
                 shared = true;
             } else if (_str.eq(arg, "-pp")) {
                 pretty = true;
+            } else if (_str.eq(arg, "-ls")) {
+                ls = true;
             } else if (_str.eq(arg, "-o")) {
                 if (i+1u < len) {
                     output_file = some(args.(i+1u));
@@ -214,8 +218,9 @@ impure fn main(vec[str] args) {
             auto env = default_environment(sess, args.(0), ifile);
             if (pretty) {
                 pretty_print_input(sess, env, ifile);
-            }
-            else {
+            } else if (ls) {
+                front.creader.list_file_metadata(ifile, std.io.stdout());
+            } else {
                 alt (output_file) {
                     case (none[str]) {
                         let vec[str] parts = _str.split(ifile, '.' as u8);