diff --git a/src/servo/gfx/pngsink.rs b/src/servo/gfx/pngsink.rs
index d3dfb55b0b1..b34345990a2 100644
--- a/src/servo/gfx/pngsink.rs
+++ b/src/servo/gfx/pngsink.rs
@@ -77,9 +77,9 @@ fn do_draw(sender: chan<AzDrawTargetRef>,
 
     listen(|data_ch: chan<[u8]>| {
 
-        crust fn write_fn(closure: *c_void,
-                          data: *c_uchar,
-                          len: c_uint)
+        extern fn write_fn(closure: *c_void,
+                           data: *c_uchar,
+                           len: c_uint)
 
             -> cairo_status_t unsafe {
 
diff --git a/src/servo/platform/osmain.rs b/src/servo/platform/osmain.rs
index a0e304f3cb3..9dada23729b 100644
--- a/src/servo/platform/osmain.rs
+++ b/src/servo/platform/osmain.rs
@@ -271,7 +271,7 @@ mod platform {
     }
 
     mod MainObj {
-         crust fn applicationDidFinishLaunching(this: id, _sel: SEL) {
+         extern fn applicationDidFinishLaunching(this: id, _sel: SEL) {
 	         #debug("applicationDidFinishLaunching");
 
 	         let fptr: *fn() = ptr::null();
diff --git a/src/servo/text/shaper.rs b/src/servo/text/shaper.rs
index 3e029064d4d..0a0dfdfd422 100644
--- a/src/servo/text/shaper.rs
+++ b/src/servo/text/shaper.rs
@@ -101,7 +101,7 @@ fn shape_text(font: &Font, text: str) -> [Glyph] unsafe {
     ret glyphs;
 }
 
-crust fn glyph_func(_font: *hb_font_t,
+extern fn glyph_func(_font: *hb_font_t,
                     font_data: *c_void,
                     unicode: hb_codepoint_t,
                     _variant_selector: hb_codepoint_t,
@@ -122,10 +122,10 @@ crust fn glyph_func(_font: *hb_font_t,
     } as hb_bool_t;
 }
 
-crust fn glyph_h_advance_func(_font: *hb_font_t,
-                              font_data: *c_void,
-                              glyph: hb_codepoint_t,
-                              _user_data: *c_void) -> hb_position_t unsafe {
+extern fn glyph_h_advance_func(_font: *hb_font_t,
+                               font_data: *c_void,
+                               glyph: hb_codepoint_t,
+                               _user_data: *c_void) -> hb_position_t unsafe {
     let font: *Font = reinterpret_cast(font_data);
     assert font.is_not_null();