[clang] [Clang] Make '-frtlib-add-rpath' include the standard library directory (PR #86217)

[Joseph Huber via cfe-commits]

https://github.com/jhuber6 updated https://github.com/llvm/llvm-project/pull/86217

>From 722b8b454d652b3d52e20b9bacff58e096cc7feb Mon Sep 17 00:00:00 2001
From: Joseph Huber <huberjn at outlook.com>
Date: Thu, 21 Mar 2024 18:25:35 -0500
Subject: [PATCH] [Clang] Make '-frtlib-add-rpath' include the standard library
 directory

Summary:
The original intention of the `openmp-add-rpath` option was to add the
rpath to the language runtime directory. However, the current
implementation only adds it to the compiler's resource directory. This
patch adds support for appending the `-rpath` to the compiler's standard
library directory as well. Currently this is `<exe>/../lib/<triple>`.
---
 clang/lib/Driver/ToolChains/CommonArgs.cpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/clang/lib/Driver/ToolChains/CommonArgs.cpp b/clang/lib/Driver/ToolChains/CommonArgs.cpp
index 4478865313636d..6b1fbba7abd031 100644
--- a/clang/lib/Driver/ToolChains/CommonArgs.cpp
+++ b/clang/lib/Driver/ToolChains/CommonArgs.cpp
@@ -1142,7 +1142,11 @@ void tools::addArchSpecificRPath(const ToolChain &TC, const ArgList &Args,
                     options::OPT_fno_rtlib_add_rpath, false))
     return;
 
-  for (const auto &CandidateRPath : TC.getArchSpecificLibPaths()) {
+  SmallVector<std::string> CandidateRPaths(TC.getArchSpecificLibPaths());
+  if (const auto CandidateRPath = TC.getStdlibPath())
+    CandidateRPaths.emplace_back(*CandidateRPath);
+
+  for (const auto &CandidateRPath : CandidateRPaths) {
     if (TC.getVFS().exists(CandidateRPath)) {
       CmdArgs.push_back("-rpath");
       CmdArgs.push_back(Args.MakeArgString(CandidateRPath));