3 files changed, 18 insertions, 2 deletions
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index b1bdc0fb7a2..38f457ada69 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -173,7 +173,10 @@ void CodeGenModule::Release() {
   EmitCtorList(GlobalDtors, "llvm.global_dtors");
   EmitGlobalAnnotations();
   EmitLLVMUsed();
-  EmitModuleLinkOptions();
+
+  if (CodeGenOpts.ModulesAutolink) {
+    EmitModuleLinkOptions();
+  }
 
   SimplifyPersonality();
 
diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index 9ef346906b1..547d45c2d8f 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -2622,12 +2622,24 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
   // -fmodules enables modules (off by default). However, for C++/Objective-C++,
   // users must also pass -fcxx-modules. The latter flag will disappear once the
   // modules implementation is solid for C++/Objective-C++ programs as well.
+  bool HaveModules = false;
   if (Args.hasFlag(options::OPT_fmodules, options::OPT_fno_modules, false)) {
     bool AllowedInCXX = Args.hasFlag(options::OPT_fcxx_modules, 
                                      options::OPT_fno_cxx_modules, 
                                      false);
-    if (AllowedInCXX || !types::isCXX(InputType))
+    if (AllowedInCXX || !types::isCXX(InputType)) {
       CmdArgs.push_back("-fmodules");
+      HaveModules = true;
+    }
+  }
+
+  // -fmodules-autolink (on by default when modules is enabled) automatically
+  // links against libraries for imported modules.
+  if (HaveModules &&
+      Args.hasFlag(options::OPT_fmodules_autolink,
+                   options::OPT_fno_modules_autolink,
+                   true)) {
+    CmdArgs.push_back("-fmodules-autolink");
   }
 
   // -faccess-control is default.
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 20def5e480c..e810a22dce0 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -332,6 +332,7 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
   }
   Opts.DebugColumnInfo = Args.hasArg(OPT_dwarf_column_info);
 
+  Opts.ModulesAutolink = Args.hasArg(OPT_fmodules_autolink);
   Opts.DisableLLVMOpts = Args.hasArg(OPT_disable_llvm_optzns);
   Opts.DisableRedZone = Args.hasArg(OPT_disable_red_zone);
   Opts.ForbidGuardVariables = Args.hasArg(OPT_fforbid_guard_variables);