[Driver][SYCL] Fix processing for partial link step with static archives (#2661)

When encountering specific linker specific arguments (-rpath) we do
not pass them along to the partial link step.  Improve the processing
for these options for cases where -Xlinker <arg1> -Xlinker <arg2> is
used.

Author: mdtoguchi

clang/lib/Driver/Driver.cpp

@@ -2679,7 +2679,11 @@ static SmallVector<const char *, 16> getLinkerArgs(Compilation &C,
         A->getOption().matches(options::OPT_Xlinker)) {
       // Parse through additional linker arguments that are meant to go
       // directly to the linker.
-      std::string PrevArg;
+      // Keep the previous arg even if it is a new argument, for example:
+      //   -Xlinker -rpath -Xlinker <dir>.
+      // Without this history, we do not know that <dir> was assocated with
+      // -rpath and is processed incorrectly.
+      static std::string PrevArg;
       for (const std::string &Value : A->getValues()) {
         auto addKnownValues = [&](const StringRef &V) {
           // Only add named static libs objects and --whole-archive options.

clang/test/Driver/sycl-offload-static-lib-2.cpp

@@ -93,7 +93,8 @@
 /// test behaviors for special case handling of -z and -rpath
 // RUN: %clangxx -target x86_64-unknown-linux-gnu -fsycl -z anystring -L/dummy/dir %t.o -Wl,-rpath,nopass -Wl,-z,nopass %t.a %t_2.a -### 2>&1 \
 // RUN:   | FileCheck %s -check-prefixes=WL_CHECK
-// WL_CHECK-NOT: ld{{.*}} "-r" {{.*}} "anystring"
+// RUN: %clangxx -target x86_64-unknown-linux-gnu -fsycl -z anystring -L/dummy/dir %t.o -Wl,-rpath -Wl,nopass -Xlinker -z -Xlinker nopass %t.a %t_2.a -### 2>&1 \
+// WL_CHECK-NOT: ld{{.*}} "-r" {{.*}} "anystring" {{.*}} "nopass"
 // WL_CHECK: ld{{.*}} "-z" "anystring" {{.*}} "-rpath" "nopass" "-z" "nopass"
 
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