Adapt code to latest rustc master changes

Author: denismerigoux

src/librustc_codegen_llvm/debuginfo/metadata.rs

@@ -2013,13 +2013,7 @@ pub fn create_vtable_metadata(
         llvm::LLVMRustDIBuilderCreateStaticVariable(DIB(cx),
                                                     NO_SCOPE_METADATA,
                                                     name.as_ptr(),
-                                                    // LLVM 3.9
-                                                    // doesn't accept
-                                                    // null here, so
-                                                    // pass the name
-                                                    // as the linkage
-                                                    // name.
-                                                    name.as_ptr(),
+                                                    ptr::null(),
                                                     unknown_file_metadata(cx),
                                                     UNKNOWN_LINE_NUMBER,
                                                     vtable_type,

src/librustc_codegen_llvm/declare.rs

@@ -23,7 +23,7 @@
 use llvm;
 use llvm::AttributePlace::Function;
 use rustc::ty::{self, PolyFnSig};
-use rustc::ty::layout::{self, LayoutOf};
+use rustc::ty::layout::LayoutOf;
 use rustc::session::config::Sanitizer;
 use rustc_data_structures::small_c_str::SmallCStr;
 use rustc_target::spec::PanicStrategy;
@@ -144,7 +144,7 @@ impl DeclareMethods<'tcx> for CodegenCx<'ll, 'tcx> {
         let fty = FnType::new(self, sig, &[]);
         let llfn = declare_raw_fn(self, name, fty.llvm_cconv(), fty.llvm_type(self));
 
-        if self.layout_of(sig.output()).abi == layout::Abi::Uninhabited {
+        if self.layout_of(sig.output()).abi.is_uninhabited() {
             llvm::Attribute::NoReturn.apply_llfn(Function, llfn);
         }