[Clang] Fix missing - in argument to nvlinker

Author: jhuber6

clang/lib/Driver/ToolChains/Cuda.cpp

@@ -635,7 +635,7 @@ void NVPTX::Linker::ConstructJob(Compilation &C, const JobAction &JA,
   getNVPTXTargetFeatures(C.getDriver(), getToolChain().getTriple(), Args,
                          Features);
   CmdArgs.push_back(
-      Args.MakeArgString("--plugin-opt=mattr=" + llvm::join(Features, ",")));
+      Args.MakeArgString("--plugin-opt=-mattr=" + llvm::join(Features, ",")));
 
   // Add paths for the default clang library path.
   SmallString<256> DefaultLibPath =

clang/test/Driver/cuda-cross-compiling.c

@@ -104,4 +104,4 @@
 // RUN: %clang -target nvptx64-nvidia-cuda --cuda-feature=+ptx63 -march=sm_52 -### %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=FEATURE %s
 
-// FEATURE: clang-nvlink-wrapper{{.*}}"--plugin-opt=mattr=+ptx63"
+// FEATURE: clang-nvlink-wrapper{{.*}}"--plugin-opt=-mattr=+ptx63"