rustc: Determine the crate type (lib/bin) in the session, not session opts

This is in preparation for adding a #[crate_type] attribute

src/comp/back/link.rs

@@ -425,7 +425,7 @@ fn build_link_meta(sess: session::session, c: ast::crate, output: str,
     }
 
     fn warn_missing(sess: session::session, name: str, default: str) {
-        if !sess.get_opts().library { ret; }
+        if !sess.building_library() { ret; }
         sess.warn(#fmt["missing crate link meta '%s', using '%s' as default",
                        name, default]);
     }
@@ -611,7 +611,7 @@ fn link_binary(sess: session::session,
     let used_libs = cstore::get_used_libraries(cstore);
     for l: str in used_libs { gcc_args += ["-l" + l]; }
 
-    if sess.get_opts().library {
+    if sess.building_library() {
         gcc_args += [lib_cmd];
 
         // On mac we need to tell the linker to let this library

src/comp/driver/rustc.rs

@@ -282,6 +282,7 @@ options:
 
     -o <filename>      write output to <filename>
     --lib              compile a library crate
+    --bin              compile an executable crate (default)
     --static           use or produce static libraries
     --no-core          omit the 'core' library (used and imported by default)
     --pretty [type]    pretty-print the input instead of compiling
@@ -371,7 +372,13 @@ fn host_triple() -> str {
 
 fn build_session_options(match: getopts::match)
    -> @session::options {
-    let library = opt_present(match, "lib");
+    let crate_type = if opt_present(match, "lib") {
+        session::lib_crate
+    } else if opt_present(match, "bin") {
+        session::bin_crate
+    } else {
+        session::unknown_crate
+    };
     let static = opt_present(match, "static");
 
     let parse_only = opt_present(match, "parse-only");
@@ -435,7 +442,7 @@ fn build_session_options(match: getopts::match)
     let stack_growth = opt_present(match, "stack-growth");
     let warn_unused_imports = opt_present(match, "warn-unused-imports");
     let sopts: @session::options =
-        @{library: library,
+        @{crate_type: crate_type,
           static: static,
           libcore: libcore,
           optimize: opt_level,
@@ -495,20 +502,21 @@ fn opts() -> [getopts::opt] {
          optflag("no-verify"),
          optmulti("cfg"), optflag("test"),
          optflag("no-core"),
-         optflag("lib"), optflag("static"), optflag("gc"),
+         optflag("lib"), optflag("bin"), optflag("static"), optflag("gc"),
          optflag("stack-growth"),
          optflag("no-asm-comments"),
          optflag("warn-unused-imports")];
 }
 
 fn build_output_filenames(ifile: str, ofile: option::t<str>,
-                          sopts: @session::options)
+                          sess: session::session)
         -> @{out_filename: str, obj_filename:str} {
     let obj_filename = "";
     let saved_out_filename: str = "";
+    let sopts = sess.get_opts();
     let stop_after_codegen =
         sopts.output_type != link::output_type_exe ||
-            sopts.static && sopts.library;
+            sopts.static && sess.building_library();
     alt ofile {
       none. {
         // "-" as input file will cause the parser to read from stdin so we
@@ -533,7 +541,7 @@ fn build_output_filenames(ifile: str, ofile: option::t<str>,
             };
         obj_filename = base_filename + "." + suffix;
 
-        if sopts.library {
+        if sess.building_library() {
             saved_out_filename = std::os::dylib_filename(base_filename);
         } else {
             saved_out_filename = base_filename;
@@ -580,7 +588,6 @@ fn main(args: [str]) {
     let sopts = build_session_options(match);
     let sess = build_session(sopts);
     let ofile = getopts::opt_maybe_str(match, "o");
-    let outputs = build_output_filenames(ifile, ofile, sopts);
     let cfg = build_configuration(sess, binary, ifile);
     let pretty =
         option::map::<str,
@@ -597,9 +604,11 @@ fn main(args: [str]) {
         ret;
     }
 
+    let outputs = build_output_filenames(ifile, ofile, sess);
+
     let stop_after_codegen =
         sopts.output_type != link::output_type_exe ||
-            sopts.static && sopts.library;
+            sopts.static && sess.building_library();
 
     let temp_filename = outputs.obj_filename;
 

src/comp/driver/session.rs

@@ -13,6 +13,8 @@ tag os { os_win32; os_macos; os_linux; }
 
 tag arch { arch_x86; arch_x86_64; arch_arm; }
 
+tag crate_type { bin_crate; lib_crate; unknown_crate; }
+
 type config =
     {os: os,
      arch: arch,
@@ -24,7 +26,7 @@ type config =
 type options =
     // The crate config requested for the session, which may be combined
     // with additional crate configurations during the compile process
-    {library: bool,
+    {crate_type: crate_type,
      static: bool,
      libcore: bool,
      optimize: uint,
@@ -116,6 +118,7 @@ obj session(targ_cfg: @config,
     fn set_main_id(d: node_id) { main_fn = some(d); }
     fn get_main_id() -> option::t<node_id> { main_fn }
     fn filesearch() -> filesearch::filesearch { filesearch }
+    fn building_library() -> bool { opts.crate_type == lib_crate }
 }
 // Local Variables:
 // fill-column: 78;

src/comp/middle/resolve.rs

@@ -362,7 +362,7 @@ fn visit_fn_with_scope(e: @env, f: ast::_fn, tp: [ast::ty_param], sp: span,
     // is this a main fn declaration?
     alt name {
       some(nm) {
-        if is_main_name([nm]) && !e.sess.get_opts().library {
+        if is_main_name([nm]) && !e.sess.building_library() {
             // This is a main function -- set it in the session
             // as the main ID
             e.sess.set_main_id(id);

src/comp/middle/trans.rs

@@ -5528,7 +5528,7 @@ fn register_fn_full(ccx: @crate_ctxt, sp: span, path: [str], _flav: str,
     ccx.item_ids.insert(node_id, llfn);
     ccx.item_symbols.insert(node_id, ps);
 
-    let is_main: bool = is_main_name(path) && !ccx.sess.get_opts().library;
+    let is_main: bool = is_main_name(path) && !ccx.sess.building_library();
     if is_main { create_main_wrapper(ccx, sp, llfn, node_type); }
 }
 
@@ -5951,7 +5951,7 @@ fn decl_crate_map(sess: session::session, mapname: str,
     let n_subcrates = 1;
     let cstore = sess.get_cstore();
     while cstore::have_crate_data(cstore, n_subcrates) { n_subcrates += 1; }
-    let mapname = sess.get_opts().library ? mapname : "toplevel";
+    let mapname = sess.building_library() ? mapname : "toplevel";
     let sym_name = "_rust_crate_map_" + mapname;
     let arrtype = T_array(int_type, n_subcrates as uint);
     let maptype = T_struct([int_type, arrtype]);
@@ -5983,7 +5983,7 @@ fn fill_crate_map(ccx: @crate_ctxt, map: ValueRef) {
 }
 
 fn write_metadata(cx: @crate_ctxt, crate: @ast::crate) {
-    if !cx.sess.get_opts().library { ret; }
+    if !cx.sess.building_library() { ret; }
     let llmeta = C_postr(metadata::encoder::encode_metadata(cx, crate));
     let llconst = trans_common::C_struct([llmeta]);
     let llglobal =

src/comp/middle/typeck.rs

@@ -2720,7 +2720,7 @@ fn check_main_fn_ty(tcx: ty::ctxt, main_id: ast::node_id) {
 }
 
 fn check_for_main_fn(tcx: ty::ctxt, crate: @ast::crate) {
-    if !tcx.sess.get_opts().library {
+    if !tcx.sess.building_library() {
         alt tcx.sess.get_main_id() {
           some(id) { check_main_fn_ty(tcx, id); }
           none. { tcx.sess.span_err(crate.span, "main function not found"); }