[llvm] [Support] Resolve symlinks in `getMainExecutable()` on Windows (PR #76304)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-llvm-support

Author: Alexandre Ganea (aganea)

<details>
<summary>Changes</summary>

This makes the Windows implementation for `getMainExecutable()` behave the same as its Linux counterpart, in regards to symlinks. Previously, when using `cmake ... -DLLVM_USE_SYMLINKS=ON`, calling this function wouldn't resolve to the "real", non-symlinked path.

---
Full diff: https://github.com/llvm/llvm-project/pull/76304.diff


1 Files Affected:

- (modified) llvm/lib/Support/Windows/Path.inc (+4-1) 


``````````diff
diff --git a/llvm/lib/Support/Windows/Path.inc b/llvm/lib/Support/Windows/Path.inc
index 168a63bb2d969d..6b50309be94d77 100644
--- a/llvm/lib/Support/Windows/Path.inc
+++ b/llvm/lib/Support/Windows/Path.inc
@@ -154,7 +154,10 @@ std::string getMainExecutable(const char *argv0, void *MainExecAddr) {
     return "";
 
   llvm::sys::path::make_preferred(PathNameUTF8);
-  return std::string(PathNameUTF8.data());
+
+  SmallString<256> RealPath;
+  sys::fs::real_path(PathNameUTF8, RealPath);
+  return (std::string)RealPath;
 }
 
 UniqueID file_status::getUniqueID() const {

``````````

</details>


https://github.com/llvm/llvm-project/pull/76304