Imply linker arguments from '-fveclib' option.

[mzolotukhin]

Summary

As discussed in D8097, we should provide corresponding linking flags when 'fveclib' is specified.

[hfinkel]

lib/Driver/Tools.cpp

6127

This also need to be guarded by:

(!Args.hasArg(options::OPT_nostdlib) &&
 !Args.hasArg(options::OPT_nodefaultlibs))

(and please update the test as well)

[mzolotukhin]

• Guard adding framework 'Accelerate' by nostdlib and nodefaultlibs.

[hfinkel]

LGTM.

lib/Driver/Tools.cpp

void darwin::Link::ConstructJob(Compilation &C, const JobAction &JA,
   Args.AddAllArgs(CmdArgs, options::OPT_F);
 
   // -iframework should be forwarded as -F.
   for (auto it = Args.filtered_begin(options::OPT_iframework),
          ie = Args.filtered_end(); it != ie; ++it)
     CmdArgs.push_back(Args.MakeArgString(std::string("-F") +
                                          (*it)->getValue()));
 
+  if (Arg *A = Args.getLastArg(options::OPT_fveclib)) {
+    if (A->getValue() == StringRef("Accelerate")) {
+      CmdArgs.push_back("-framework");
+      CmdArgs.push_back("Accelerate");
+    }
+  }
+
   const char *Exec =
     Args.MakeArgString(getToolChain().GetLinkerPath());
   std::unique_ptr<Command> Cmd =
     llvm::make_unique<Command>(JA, *this, Exec, CmdArgs);
   Cmd->setInputFileList(std::move(InputFileList));
   C.addCommand(std::move(Cmd));
 }
 

test/Driver/fveclib.c

 // RUN: %clang -### -c -fveclib=none %s 2>&1 | FileCheck -check-prefix CHECK-NOLIB %s
 // RUN: %clang -### -c -fveclib=Accelerate %s 2>&1 | FileCheck -check-prefix CHECK-ACCELERATE %s
 // RUN: not %clang -c -fveclib=something %s 2>&1 | FileCheck -check-prefix CHECK-INVALID %s
 
 // CHECK-NOLIB: "-fveclib=none"
 // CHECK-ACCELERATE: "-fveclib=Accelerate"
 
 // CHECK-INVALID: error: invalid value 'something' in '-fveclib=something'
+
+// RUN: %clang -fveclib=Accelerate %s -target arm64-apple-ios8.0.0 -### 2>&1 | FileCheck --check-prefix=CHECK-LINK %s
+// CHECK-LINK: "-framework" "Accelerate"