[llvm] [llvm-objdump] Fix mcpuHelp() memory leak (PR #172525)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-llvm-binary-utilities

Author: Ruoyu Qiu (cabbaken)

<details>
<summary>Changes</summary>

The call to `DummyTarget->createMCSubtargetInfo` within `mcpuHelp()` returns a pointer that is not subsequently freed, leading to a memory leak.
Use std::unique_ptr to ensure the memory is released automatically.

---
Full diff: https://github.com/llvm/llvm-project/pull/172525.diff


1 Files Affected:

- (modified) llvm/tools/llvm-objdump/llvm-objdump.cpp (+2-1) 


``````````diff
diff --git a/llvm/tools/llvm-objdump/llvm-objdump.cpp b/llvm/tools/llvm-objdump/llvm-objdump.cpp
index 97032eca5f2d1..7fd0eed151b17 100644
--- a/llvm/tools/llvm-objdump/llvm-objdump.cpp
+++ b/llvm/tools/llvm-objdump/llvm-objdump.cpp
@@ -3581,7 +3581,8 @@ static void mcpuHelp() {
   if (!DummyTarget)
     reportCmdLineError(ErrMessage);
   // We need to access the Help() through the corresponding MCSubtargetInfo.
-  DummyTarget->createMCSubtargetInfo(TheTriple, "help", "");
+  std::unique_ptr<MCSubtargetInfo> MSI(
+      DummyTarget->createMCSubtargetInfo(TheTriple.str(), "help", ""));
 }
 
 static void parseOtoolOptions(const llvm::opt::InputArgList &InputArgs) {

``````````

</details>


https://github.com/llvm/llvm-project/pull/172525