[COFF] Statically link certain runtime library functions

Statically link certain runtime library functions for MSVC/GNU Windows
environments. This is consistent with MSVC behavior.

Fixes LNK4286 and LNK4217 warnings from link.exe when linking the static
CRT:
  LINK : warning LNK4286: symbol '__std_terminate' defined in 'libvcruntime.lib(ehhelpers.obj)' is imported by 'ASAN_NOINST_TEST_OBJECTS.asan_noinst_test.cc.x86_64-calls.o'
  LINK : warning LNK4286: symbol '__std_terminate' defined in 'libvcruntime.lib(ehhelpers.obj)' is imported by 'ASAN_NOINST_TEST_OBJECTS.asan_test_main.cc.x86_64-calls.o'
  LINK : warning LNK4217: symbol '_CxxThrowException' defined in 'libvcruntime.lib(throw.obj)' is imported by 'ASAN_NOINST_TEST_OBJECTS.gtest-all.cc.x86_64-calls.o' in function '"int `public: static class UnitTest::GetInstance * __cdecl testing::UnitTest::GetInstance(void)'::`1'::dtor$5" (?dtor$5@?0??GetInstance@UnitTest@testing@@SAPEAV12@XZ@4HA)'

Reviewers: mstorsjo, efriedma, TomTan, compnerd, smeenai, mgrang

Subscribers: abdulras, theraven, smeenai, pcc, mehdi_amini, javed.absar, inglorion, kristof.beyls, dexonsmith, cfe-commits

Differential Revision: https://reviews.llvm.org/D55229

llvm-svn: 359250

5 files changed, 31 insertions, 8 deletions

diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index e51963aa9af..b490fa0faf2 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -3000,9 +3000,13 @@ CodeGenModule::CreateRuntimeFunction(llvm::FunctionType *FTy, StringRef Name,
     if (F->empty()) {
       F->setCallingConv(getRuntimeCC());
 
-      if (!Local && getTriple().isOSBinFormatCOFF() &&
-          !getCodeGenOpts().LTOVisibilityPublicStd &&
-          !getTriple().isWindowsGNUEnvironment()) {
+      // In Windows Itanium environments, try to mark runtime functions
+      // dllimport. For Mingw and MSVC, don't. We don't really know if the user
+      // will link their standard library statically or dynamically. Marking
+      // functions imported when they are not imported can cause linker errors
+      // and warnings.
+      if (!Local && getTriple().isWindowsItaniumEnvironment() &&
+          !getCodeGenOpts().LTOVisibilityPublicStd) {
         const FunctionDecl *FD = GetRuntimeFunctionDecl(Context, Name);
         if (!FD || FD->hasAttr<DLLImportAttr>()) {
           F->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass);
diff --git a/clang/test/CodeGen/ms-symbol-linkage.cpp b/clang/test/CodeGen/ms-symbol-linkage.cpp
new file mode 100644
index 00000000000..3674ad0debf
--- /dev/null
+++ b/clang/test/CodeGen/ms-symbol-linkage.cpp
@@ -0,0 +1,20 @@
+// RUN: %clangxx -target aarch64-windows \
+// RUN: -fcxx-exceptions -c -o - %s \
+// RUN: | llvm-objdump -syms - 2>&1 | FileCheck %s
+
+void foo1() { throw 1; }
+// CHECK-LABEL: foo1
+// CHECK-NOT: __imp__CxxThrowException
+
+void bar();
+void foo2() noexcept(true) { bar(); }
+// CHECK-LABEL: foo2
+// CHECK-NOT: __imp___std_terminate
+
+struct A {};
+struct B { virtual void f(); };
+struct C : A, virtual B {};
+struct T {};
+T *foo3() { return dynamic_cast<T *>((C *)0); }
+// CHECK-LABEL: foo3
+// CHECK-NOT: __imp___RTDynamicCast
diff --git a/clang/test/CodeGenCXX/runtime-dllstorage.cpp b/clang/test/CodeGenCXX/runtime-dllstorage.cpp
index 7220fa50b0e..3c0c73f9aa3 100644
--- a/clang/test/CodeGenCXX/runtime-dllstorage.cpp
+++ b/clang/test/CodeGenCXX/runtime-dllstorage.cpp
@@ -108,7 +108,7 @@ void l() {
 // CHECK-MS-DAG: @_Init_thread_epoch = external thread_local global i32
 // CHECK-MS-DAG: declare dso_local i32 @__tlregdtor(void ()*)
 // CHECK-MS-DAG: declare dso_local i32 @atexit(void ()*)
-// CHECK-MS-DYNAMIC-DAG: declare dllimport {{.*}} void @_CxxThrowException
+// CHECK-MS-DYNAMIC-DAG: declare {{.*}} void @_CxxThrowException
 // CHECK-MS-STATIC-DAG: declare {{.*}} void @_CxxThrowException
 // CHECK-MS-DAG: declare dso_local noalias i8* @"??2@YAPAXI@Z"
 // CHECK-MS-DAG: declare dso_local void @_Init_thread_header(i32*)
diff --git a/clang/test/CodeGenObjC/gnu-init.m b/clang/test/CodeGenObjC/gnu-init.m
index 32db49fdf90..6d562b80cb9 100644
--- a/clang/test/CodeGenObjC/gnu-init.m
+++ b/clang/test/CodeGenObjC/gnu-init.m
@@ -100,6 +100,6 @@
 // Check our load function is in a comdat.
 // CHECK-WIN: define linkonce_odr hidden void @.objcv2_load_function() comdat {
 
-// Make sure we have dllimport on the load function
-// CHECK-WIN: declare dllimport void @__objc_load
+// Make sure we do not have dllimport on the load function
+// CHECK-WIN: declare dso_local void @__objc_load
 
diff --git a/clang/test/CodeGenObjCXX/msabi-stret.mm b/clang/test/CodeGenObjCXX/msabi-stret.mm
index 765c23887ba..66e407af27e 100644
--- a/clang/test/CodeGenObjCXX/msabi-stret.mm
+++ b/clang/test/CodeGenObjCXX/msabi-stret.mm
@@ -13,6 +13,5 @@ S f() {
   return [I m:S()];
 }
 
-// CHECK: declare dllimport void @objc_msgSend_stret(i8*, i8*, ...)
+// CHECK: declare dso_local void @objc_msgSend_stret(i8*, i8*, ...)
 // CHECK-NOT: declare dllimport void @objc_msgSend(i8*, i8*, ...)
-