[Driver][SYCL] Suppress link warning when dealing with device binaries (#3449)

When performing a link with SYCL device binaries on Windows, a warning
is emitted due to the length of the section string used.  They are not
unique up to 32 characters, causing the linker to emit a warning.
Suppress this warning when we are dealing with -fsycl

Author: mdtoguchi

clang/lib/Driver/ToolChains/MSVC.cpp

@@ -389,6 +389,11 @@ void visualstudio::Linker::constructMSVCLibCommand(Compilation &C,
   if (Args.hasArg(options::OPT_fsycl_link_EQ) &&
       Args.hasArg(options::OPT_fintelfpga))
     CmdArgs.push_back("/IGNORE:4221");
+
+  // Suppress multiple section warning LNK4078
+  if (Args.hasFlag(options::OPT_fsycl, options::OPT_fno_sycl, false))
+    CmdArgs.push_back("/IGNORE:4078");
+
   CmdArgs.push_back(
       C.getArgs().MakeArgString(Twine("-OUT:") + Output.getFilename()));
 
@@ -443,6 +448,10 @@ void visualstudio::Linker::ConstructJob(Compilation &C, const JobAction &JA,
     CmdArgs.push_back(
         Args.MakeArgString(Twine("-wholearchive:") + A->getValue()));
 
+  // Suppress multiple section warning LNK4078
+  if (Args.hasFlag(options::OPT_fsycl, options::OPT_fno_sycl, false))
+    CmdArgs.push_back("/IGNORE:4078");
+
   // If the VC environment hasn't been configured (perhaps because the user
   // did not run vcvarsall), try to build a consistent link environment.  If
   // the environment variable is set however, assume the user knows what

clang/test/Driver/suppress-LNK4078-sycl-link.cpp

@@ -0,0 +1,14 @@
+// REQUIRES: clang-driver
+// RUN:  %clangxx -target x86_64-pc-windows-msvc -fsycl %s -### 2>&1 \
+// RUN:  | FileCheck %s
+// RUN:  %clang_cl --target=x86_64-pc-windows-msvc -fsycl %s -### 2>&1 \
+// RUN:  | FileCheck %s
+// RUN:  %clangxx -target x86_64-pc-windows-msvc -fsycl -fintelfpga -fsycl-link=early %s -### 2>&1 \
+// RUN:  | FileCheck %s
+// RUN:  %clangxx -target x86_64-pc-windows-msvc -fsycl -fintelfpga -fsycl-link=image %s -### 2>&1 \
+// RUN:  | FileCheck %s
+// RUN:  %clang_cl --target=x86_64-pc-windows-msvc -fsycl -fintelfpga -fsycl-link=early %s -### 2>&1 \
+// RUN:  | FileCheck %s
+// RUN:  %clang_cl --target=x86_64-pc-windows-msvc -fsycl -fintelfpga -fsycl-link=image %s -### 2>&1 \
+// RUN:  | FileCheck %s
+// CHECK: /IGNORE:4078