auto merge of #14643 : jakub-/rust/infinite-loop-unreachable, r=alexcrichton

[rust.git] / src / librustc / middle / trans / controlflow.rs

diff --git a/src/librustc/middle/trans/controlflow.rs b/src/librustc/middle/trans/controlflow.rs
index 7905436a7a3ada32afd78b2bdca56cbc03c43762..eac7af56ed4c00bd371c181273500e4c30fa0e54 100644 (file)
--- a/src/librustc/middle/trans/controlflow.rs
+++ b/src/librustc/middle/trans/controlflow.rs
@@ -9,21 +9,20 @@
 // except according to those terms.
 
 use lib::llvm::*;
-use driver::session::FullDebugInfo;
+use driver::config::FullDebugInfo;
 use middle::lang_items::{FailFnLangItem, FailBoundsCheckFnLangItem};
 use middle::trans::base::*;
 use middle::trans::build::*;
 use middle::trans::callee;
+use middle::trans::cleanup::CleanupMethods;
+use middle::trans::cleanup;
 use middle::trans::common::*;
 use middle::trans::debuginfo;
-use middle::trans::cleanup;
-use middle::trans::cleanup::CleanupMethods;
 use middle::trans::expr;
+use middle::trans::type_of;
 use middle::ty;
 use util::ppaux::Repr;
 
-use middle::trans::type_::Type;
-
 use syntax::ast;
 use syntax::ast::Ident;
 use syntax::ast_util;
@@ -40,7 +39,7 @@ pub fn trans_stmt<'a>(cx: &'a Block<'a>,
     debug!("trans_stmt({})", s.repr(cx.tcx()));
 
     if cx.sess().asm_comments() {
-        add_span_comment(cx, s.span, s.repr(cx.tcx()));
+        add_span_comment(cx, s.span, s.repr(cx.tcx()).as_slice());
     }
 
     let mut bcx = cx;
@@ -165,7 +164,7 @@ pub fn trans_if<'a>(bcx: &'a Block<'a>,
     }
 
     let name = format!("then-block-{}-", thn.id);
-    let then_bcx_in = bcx.fcx.new_id_block(name, thn.id);
+    let then_bcx_in = bcx.fcx.new_id_block(name.as_slice(), thn.id);
     let then_bcx_out = trans_block(then_bcx_in, thn, dest);
     debuginfo::clear_source_location(bcx.fcx);
 
@@ -265,6 +264,10 @@ pub fn trans_loop<'a>(bcx:&'a Block<'a>,
 
     fcx.pop_loop_cleanup_scope(loop_id);
 
+    if ty::type_is_bot(node_id_type(bcx, loop_id)) {
+        Unreachable(next_bcx_in);
+    }
+
     return next_bcx_in;
 }
 
@@ -287,7 +290,8 @@ pub fn trans_break_cont<'a>(bcx: &'a Block<'a>,
             match bcx.tcx().def_map.borrow().find(&expr_id) {
                 Some(&ast::DefLabel(loop_id)) => loop_id,
                 ref r => {
-                    bcx.tcx().sess.bug(format!("{:?} in def-map for label", r))
+                    bcx.tcx().sess.bug(format!("{:?} in def-map for label",
+                                               r).as_slice())
                 }
             }
         }
@@ -336,19 +340,31 @@ pub fn trans_ret<'a>(bcx: &'a Block<'a>,
     return bcx;
 }
 
+fn str_slice_arg<'a>(bcx: &'a Block<'a>, s: InternedString) -> ValueRef {
+    let ccx = bcx.ccx();
+    let t = ty::mk_str_slice(bcx.tcx(), ty::ReStatic, ast::MutImmutable);
+    let s = C_str_slice(ccx, s);
+    let slot = alloca(bcx, val_ty(s), "__temp");
+    Store(bcx, s, slot);
+
+    // The type of C_str_slice is { i8*, i64 }, but the type of the &str is
+    // %str_slice, so we do a bitcast here to the right type.
+    BitCast(bcx, slot, type_of::type_of(ccx, t).ptr_to())
+}
+
 pub fn trans_fail<'a>(
                   bcx: &'a Block<'a>,
                   sp: Span,
                   fail_str: InternedString)
                   -> &'a Block<'a> {
     let ccx = bcx.ccx();
-    let v_fail_str = C_cstr(ccx, fail_str, true);
     let _icx = push_ctxt("trans_fail_value");
+
+    let v_str = str_slice_arg(bcx, fail_str);
     let loc = bcx.sess().codemap().lookup_char_pos(sp.lo);
-    let v_filename = C_cstr(ccx, token::intern_and_get_ident(loc.file.name), true);
+    let filename = token::intern_and_get_ident(loc.file.name.as_slice());
+    let v_filename = str_slice_arg(bcx, filename);
     let v_line = loc.line as int;
-    let v_str = PointerCast(bcx, v_fail_str, Type::i8p(ccx));
-    let v_filename = PointerCast(bcx, v_filename, Type::i8p(ccx));
     let args = vec!(v_str, v_filename, C_int(ccx, v_line));
     let did = langcall(bcx, Some(sp), "", FailFnLangItem);
     let bcx = callee::trans_lang_call(bcx,
@@ -366,7 +382,14 @@ pub fn trans_fail_bounds_check<'a>(
                                len: ValueRef)
                                -> &'a Block<'a> {
     let _icx = push_ctxt("trans_fail_bounds_check");
-    let (filename, line) = filename_and_line_num_from_span(bcx, sp);
+
+    // Extract the file/line from the span
+    let loc = bcx.sess().codemap().lookup_char_pos(sp.lo);
+    let filename = token::intern_and_get_ident(loc.file.name.as_slice());
+
+    // Invoke the lang item
+    let filename = str_slice_arg(bcx, filename);
+    let line = C_int(bcx.ccx(), loc.line as int);
     let args = vec!(filename, line, index, len);
     let did = langcall(bcx, Some(sp), "", FailBoundsCheckFnLangItem);
     let bcx = callee::trans_lang_call(bcx,