Fix to combine into an object file when needed

Author: antoyo

src/back/lto.rs

@@ -10,6 +10,7 @@
 use std::ffi::CString;
 use std::fs::{self, File};
 use std::path::{Path, PathBuf};
+use std::sync::atomic::Ordering;
 
 use gccjit::OutputKind;
 use object::read::archive::ArchiveFile;
@@ -28,7 +29,7 @@ use tempfile::{TempDir, tempdir};
 
 use crate::back::write::save_temp_bitcode;
 use crate::errors::{
-    DynamicLinkingWithLTO, LoadBitcode, LtoBitcodeFromRlib, LtoDisallowed, LtoDylib,
+    DynamicLinkingWithLTO, LtoBitcodeFromRlib, LtoDisallowed, LtoDylib,
 };
 use crate::{GccCodegenBackend, GccContext};
 
@@ -250,8 +251,6 @@ fn fat_lto(cgcx: &CodegenContext<GccCodegenBackend>, diag_handler: &Handler, mod
     };
     let mut serialized_bitcode = Vec::new();
     {
-        let context = &module.module_llvm.context;
-        println!("Base module: {}", module.name);
         info!("using {:?} as a base module", module.name);
 
         // For all other modules we codegened we'll need to link them into our own
@@ -284,6 +283,7 @@ fn fat_lto(cgcx: &CodegenContext<GccCodegenBackend>, diag_handler: &Handler, mod
             info!("linking {:?}", name);
             match bc_decoded {
                 SerializedModule::Local(ref module_buffer) => {
+                    cgcx.backend.should_combine_object_files.store(true, Ordering::SeqCst);
                     module.module_llvm.context.add_driver_option(module_buffer.0.to_str().expect("path"));
                 },
                 SerializedModule::FromRlib(_) => unimplemented!("from rlib"),

src/back/write.rs

@@ -1,3 +1,4 @@
+use std::sync::atomic::Ordering;
 use std::{env, fs};
 
 use gccjit::OutputKind;
@@ -20,8 +21,7 @@ pub(crate) unsafe fn codegen(cgcx: &CodegenContext<GccCodegenBackend>, diag_hand
 
         let module_name = module.name.clone();
 
-        // FIXME: by adding a variable in CodegenContext.
-        let should_combine_object_files = module_name == "test_rust.8bd2b20a-cgu.0";
+        let should_combine_object_files = cgcx.backend.should_combine_object_files.load(Ordering::SeqCst);
 
         let module_name = Some(&module_name[..]);
 
@@ -50,16 +50,7 @@ pub(crate) unsafe fn codegen(cgcx: &CodegenContext<GccCodegenBackend>, diag_hand
                 context.add_driver_option("-flto");
                 context.add_command_line_option("-flto-partition=one");
                 context.add_driver_option("-flto-partition=one");
-                if should_combine_object_files {
-                    unimplemented!(); // TODO: remove this line.
-                    context.add_driver_option("-Wl,-r");
-                    context.add_driver_option("-nostdlib");
-                    // NOTE: this doesn't actually generate an executable. With the above flags, it combines the .o files together in another .o.
-                    context.compile_to_file(OutputKind::Executable, obj_out.to_str().expect("path to str"));
-                }
-                else {
-                    context.compile_to_file(OutputKind::ObjectFile, bc_out.to_str().expect("path to str"));
-                }
+                context.compile_to_file(OutputKind::ObjectFile, bc_out.to_str().expect("path to str"));
             }
 
             if config.emit_obj == EmitObj::ObjectCode(BitcodeSection::Full) {
@@ -68,9 +59,6 @@ pub(crate) unsafe fn codegen(cgcx: &CodegenContext<GccCodegenBackend>, diag_hand
                     .generic_activity_with_arg("GCC_module_codegen_embed_bitcode", &*module.name);
                 // TODO(antoyo): maybe we should call embed_bitcode to have the proper iOS fixes?
                 //embed_bitcode(cgcx, llcx, llmod, &config.bc_cmdline, data);
-                if should_combine_object_files {
-                    unimplemented!();
-                }
 
                 context.add_command_line_option("-flto");
                 context.add_driver_option("-flto");

src/declare.rs

@@ -1,4 +1,4 @@
-use gccjit::{Function, FunctionType, GlobalKind, LValue, RValue, Type, FnAttribute};
+use gccjit::{Function, FunctionType, GlobalKind, LValue, RValue, Type};
 use rustc_codegen_ssa::traits::BaseTypeMethods;
 use rustc_middle::ty::Ty;
 use rustc_span::Symbol;

src/lib.rs

@@ -66,6 +66,7 @@ mod type_;
 mod type_of;
 
 use std::any::Any;
+use std::sync::atomic::AtomicBool;
 use std::sync::{Arc, Mutex};
 
 use gccjit::{Context, OptimizationLevel, CType};
@@ -105,6 +106,7 @@ impl<F: Fn() -> String> Drop for PrintOnPanic<F> {
 
 #[derive(Clone)]
 pub struct GccCodegenBackend {
+    should_combine_object_files: Arc<AtomicBool>,
     supports_128bit_integers: Arc<Mutex<bool>>,
 }
 
@@ -113,7 +115,7 @@ impl CodegenBackend for GccCodegenBackend {
         crate::DEFAULT_LOCALE_RESOURCE
     }
 
-    fn init(&self, sess: &Session) {
+    fn init(&self, _sess: &Session) {
         #[cfg(feature="master")]
         gccjit::set_global_personality_function_name(b"rust_eh_personality\0");
 
@@ -212,7 +214,7 @@ impl WriteBackendMethods for GccCodegenBackend {
     type ThinData = ();
     type ThinBuffer = ThinBuffer;
 
-    fn run_fat_lto(cgcx: &CodegenContext<Self>, mut modules: Vec<FatLTOInput<Self>>, cached_modules: Vec<(SerializedModule<Self::ModuleBuffer>, WorkProduct)>) -> Result<LtoModuleCodegen<Self>, FatalError> {
+    fn run_fat_lto(cgcx: &CodegenContext<Self>, modules: Vec<FatLTOInput<Self>>, cached_modules: Vec<(SerializedModule<Self::ModuleBuffer>, WorkProduct)>) -> Result<LtoModuleCodegen<Self>, FatalError> {
         back::lto::run_fat(cgcx, modules, cached_modules)
     }
 
@@ -259,6 +261,7 @@ impl WriteBackendMethods for GccCodegenBackend {
 #[no_mangle]
 pub fn __rustc_codegen_backend() -> Box<dyn CodegenBackend> {
     Box::new(GccCodegenBackend {
+        should_combine_object_files: Arc::new(AtomicBool::new(false)),
         supports_128bit_integers: Arc::new(Mutex::new(false)),
     })
 }