rustc: Handle linker diagnostic from LLVM

Previously linker diagnostic were being hidden when two modules were linked
together but failed to link. This commit fixes the situation by ensuring that we
have a diagnostic handler installed and also adds support for handling linker
diagnostics.

diff --git a/src/librustc_codegen_llvm/back/lto.rs b/src/librustc_codegen_llvm/back/lto.rs
index daa2fb05280649793a50ac3831c7352cd8b1f5df..b644422e79532a4aba355813fff735f5d2f88a90 100644 (file)
--- a/src/librustc_codegen_llvm/back/lto.rs
+++ b/src/librustc_codegen_llvm/back/lto.rs
@@ -11,7 +11,7 @@
 use back::bytecode::{DecodedBytecode, RLIB_BYTECODE_EXTENSION};
 use back::symbol_export;
 use back::write::{ModuleConfig, with_llvm_pmb, CodegenContext};
-use back::write;
+use back::write::{self, DiagnosticHandlers};
 use errors::{FatalError, Handler};
 use llvm::archive_ro::ArchiveRO;
 use llvm::{True, False};
@@ -234,9 +234,17 @@ fn fat_lto(cgcx: &CodegenContext,
     let module = modules.remove(costliest_module);
     let mut serialized_bitcode = Vec::new();
     {
-        let llmod = module.llvm().expect("can't lto pre-codegened modules").llmod();
+        let (llcx, llmod) = {
+            let llvm = module.llvm().expect("can't lto pre-codegened modules");
+            (&llvm.llcx, llvm.llmod())
+        };
         info!("using {:?} as a base module", module.llmod_id);
 
+        // The linking steps below may produce errors and diagnostics within LLVM
+        // which we'd like to handle and print, so set up our diagnostic handlers
+        // (which get unregistered when they go out of scope below).
+        let _handler = DiagnosticHandlers::new(cgcx, diag_handler, llcx);
+
         // For all other modules we codegened we'll need to link them into our own
         // bitcode. All modules were codegened in their own LLVM context, however,
         // and we want to move everything to the same LLVM context. Currently the

diff --git a/src/librustc_codegen_llvm/back/write.rs b/src/librustc_codegen_llvm/back/write.rs
index db044878fe745e194b12d215cc0adc1453337e53..209c3a23c5cc35e1f6a97350825b3d61b4e5bae1 100644 (file)
--- a/src/librustc_codegen_llvm/back/write.rs
+++ b/src/librustc_codegen_llvm/back/write.rs
@@ -397,15 +397,15 @@ pub(crate) fn save_temp_bitcode(&self, module: &ModuleCodegen, name: &str) {
     }
 }
 
-struct DiagnosticHandlers<'a> {
+pub struct DiagnosticHandlers<'a> {
     data: *mut (&'a CodegenContext, &'a Handler),
     llcx: &'a llvm::Context,
 }
 
 impl<'a> DiagnosticHandlers<'a> {
-    fn new(cgcx: &'a CodegenContext,
-           handler: &'a Handler,
-           llcx: &'a llvm::Context) -> Self {
+    pub fn new(cgcx: &'a CodegenContext,
+               handler: &'a Handler,
+               llcx: &'a llvm::Context) -> Self {
         let data = Box::into_raw(Box::new((cgcx, handler)));
         unsafe {
             llvm::LLVMRustSetInlineAsmDiagnosticHandler(llcx, inline_asm_handler, data as *mut _);
@@ -475,10 +475,11 @@ fn drop(&mut self) {
                                                 opt.message));
             }
         }
-        llvm::diagnostic::PGO(diagnostic_ref) => {
+        llvm::diagnostic::PGO(diagnostic_ref) |
+        llvm::diagnostic::Linker(diagnostic_ref) => {
             let msg = llvm::build_string(|s| {
                 llvm::LLVMRustWriteDiagnosticInfoToString(diagnostic_ref, s)
-            }).expect("non-UTF8 PGO diagnostic");
+            }).expect("non-UTF8 diagnostic");
             diag_handler.warn(&msg);
         }
         llvm::diagnostic::UnknownDiagnostic(..) => {},

diff --git a/src/librustc_codegen_llvm/llvm/diagnostic.rs b/src/librustc_codegen_llvm/llvm/diagnostic.rs
index 7f2a9d6984a1577fbca34234f932f2b250e253d7..c41a5f74ae30282a598717aaa843f95fb9c348c9 100644 (file)
--- a/src/librustc_codegen_llvm/llvm/diagnostic.rs
+++ b/src/librustc_codegen_llvm/llvm/diagnostic.rs
@@ -126,6 +126,7 @@ pub enum Diagnostic<'ll> {
     Optimization(OptimizationDiagnostic<'ll>),
     InlineAsm(InlineAsmDiagnostic<'ll>),
     PGO(&'ll DiagnosticInfo),
+    Linker(&'ll DiagnosticInfo),
 
     /// LLVM has other types that we do not wrap here.
     UnknownDiagnostic(&'ll DiagnosticInfo),
@@ -168,6 +169,9 @@ pub unsafe fn unpack(di: &'ll DiagnosticInfo) -> Self {
             Dk::PGOProfile => {
                 PGO(di)
             }
+            Dk::Linker => {
+                Linker(di)
+            }
 
             _ => UnknownDiagnostic(di),
         }

diff --git a/src/librustc_codegen_llvm/llvm/ffi.rs b/src/librustc_codegen_llvm/llvm/ffi.rs
index 898d3d67353634b1ece65bfd1e2dd74fea44f9c8..989498ea92bcefd770af80cee557ac8f6741648b 100644 (file)
--- a/src/librustc_codegen_llvm/llvm/ffi.rs
+++ b/src/librustc_codegen_llvm/llvm/ffi.rs
@@ -332,6 +332,7 @@ pub enum DiagnosticKind {
     OptimizationRemarkOther,
     OptimizationFailure,
     PGOProfile,
+    Linker,
 }
 
 /// LLVMRustArchiveKind

diff --git a/src/rustllvm/RustWrapper.cpp b/src/rustllvm/RustWrapper.cpp
index f2b5297285ca79623d4ccad6e3b13d69625dda09..4bcb4fd7ad385a4ec1c0db8593a65cb578d248e6 100644 (file)
--- a/src/rustllvm/RustWrapper.cpp
+++ b/src/rustllvm/RustWrapper.cpp
@@ -984,6 +984,7 @@ enum class LLVMRustDiagnosticKind {
   OptimizationRemarkOther,
   OptimizationFailure,
   PGOProfile,
+  Linker,
 };
 
 static LLVMRustDiagnosticKind toRust(DiagnosticKind Kind) {
@@ -1008,6 +1009,8 @@ static LLVMRustDiagnosticKind toRust(DiagnosticKind Kind) {
     return LLVMRustDiagnosticKind::OptimizationRemarkAnalysisAliasing;
   case DK_PGOProfile:
     return LLVMRustDiagnosticKind::PGOProfile;
+  case DK_Linker:
+    return LLVMRustDiagnosticKind::Linker;
   default:
     return (Kind >= DK_FirstRemark && Kind <= DK_LastRemark)
                ? LLVMRustDiagnosticKind::OptimizationRemarkOther

diff --git a/src/test/compile-fail/auxiliary/lto-duplicate-symbols1.rs b/src/test/compile-fail/auxiliary/lto-duplicate-symbols1.rs
new file mode 100644 (file)
index 0000000..ea09327
--- /dev/null
+++ b/src/test/compile-fail/auxiliary/lto-duplicate-symbols1.rs
@@ -0,0 +1,16 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// no-prefer-dynamic
+
+#![crate_type = "rlib"]
+
+#[no_mangle]
+pub extern fn foo() {}

diff --git a/src/test/compile-fail/auxiliary/lto-duplicate-symbols2.rs b/src/test/compile-fail/auxiliary/lto-duplicate-symbols2.rs
new file mode 100644 (file)
index 0000000..ea09327
--- /dev/null
+++ b/src/test/compile-fail/auxiliary/lto-duplicate-symbols2.rs
@@ -0,0 +1,16 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// no-prefer-dynamic
+
+#![crate_type = "rlib"]
+
+#[no_mangle]
+pub extern fn foo() {}

diff --git a/src/test/compile-fail/lto-duplicate-symbols.rs b/src/test/compile-fail/lto-duplicate-symbols.rs
new file mode 100644 (file)
index 0000000..9c1dbfc
--- /dev/null
+++ b/src/test/compile-fail/lto-duplicate-symbols.rs
@@ -0,0 +1,20 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// aux-build:lto-duplicate-symbols1.rs
+// aux-build:lto-duplicate-symbols2.rs
+// error-pattern:Linking globals named 'foo': symbol multiply defined!
+// compile-flags: -C lto
+// no-prefer-dynamic
+
+extern crate lto_duplicate_symbols1;
+extern crate lto_duplicate_symbols2;
+
+fn main() {}