[clang-linker-wrapper] Add error handling for missing linker path

[asudarsa]

In clang-linker-wrapper, we do not explicitly check if --linker-path is provided.
This PR adds a check to capture this.

Thanks

[llvmbot]

@llvm/pr-subscribers-clang-driver

@llvm/pr-subscribers-clang

Author: Arvind Sudarsanam (asudarsa)

Changes

In clang-linker-wrapper, we do not explicitly check if --linker-path is provided.
This PR adds a check to capture this.

Thanks

---

Full diff: https://github.com/llvm/llvm-project/pull/113613.diff

2 Files Affected:

• (modified) clang/test/Driver/linker-wrapper.c (+4)
• (modified) clang/tools/clang-linker-wrapper/ClangLinkerWrapper.cpp (+2)

diff --git a/clang/test/Driver/linker-wrapper.c b/clang/test/Driver/linker-wrapper.c
index 068ea2d7d3c663..4ab4051f37553e 100644
--- a/clang/test/Driver/linker-wrapper.c
+++ b/clang/test/Driver/linker-wrapper.c
@@ -250,3 +250,7 @@ __attribute__((visibility("protected"), used)) int x;
 //       MLLVM-SAME: -Xlinker -mllvm=-pass-remarks=foo,bar
 //  OFFLOAD-OPT-NOT: -Xlinker -mllvm=-pass-remarks=foo,bar
 // OFFLOAD-OPT-SAME: {{$}}
+
+// Error handling when --linker-path is not provided for clang-linker-wrapper
+// RUN: not clang-linker-wrapper 2>&1 | FileCheck --check-prefix=LINKER-PATH-NOT-PROVIDED %s
+// LINKER-PATH-NOT-PROVIDED: Host linker is not available
diff --git a/clang/tools/clang-linker-wrapper/ClangLinkerWrapper.cpp b/clang/tools/clang-linker-wrapper/ClangLinkerWrapper.cpp
index 9fea1fdcd5fb46..8000d0e1f48dad 100644
--- a/clang/tools/clang-linker-wrapper/ClangLinkerWrapper.cpp
+++ b/clang/tools/clang-linker-wrapper/ClangLinkerWrapper.cpp
@@ -370,6 +370,8 @@ Error runLinker(ArrayRef<StringRef> Files, const ArgList &Args) {
   // Render the linker arguments and add the newly created image. We add it
   // after the output file to ensure it is linked with the correct libraries.
   StringRef LinkerPath = Args.getLastArgValue(OPT_linker_path_EQ);
+  if (LinkerPath.empty())
+    return createStringError("Host linker is not available");
   ArgStringList NewLinkerArgs;
   for (const opt::Arg *Arg : Args) {
     // Do not forward arguments only intended for the linker wrapper.

[asudarsa]

@jhuber6

Can you please take a look when convenient and comment if this change looks ok?

Thanks

[jhuber6]

Suggested change

	return createStringError("Host linker is not available");
	return createStringError("linker path missing, must pass 'linker-path'");

[asudarsa]

Thanks. Addressed in next commit.