[clang] [Haiku] Don't assume clang was build with libstdc++ as default (PR #65871)

[Alex Brachet via cfe-commits]

https://github.com/abrachet created https://github.com/llvm/llvm-project/pull/65871:

This test fails with `CLANG_DEFAULT_CXX_STDLIB=libc++`

>From 01607fcb02df7e9f91f39c01938c8b67247703bd Mon Sep 17 00:00:00 2001
From: Alex Brachet <abrachet at google.com>
Date: Sat, 9 Sep 2023 23:27:33 -0400
Subject: [PATCH] [Haiku] Don't assume clang was build with libstdc++ as
 default

This test fails with `CLANG_DEFAULT_CXX_STDLIB=libc++`
---
 clang/test/Driver/haiku.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/clang/test/Driver/haiku.cpp b/clang/test/Driver/haiku.cpp
index f022013d1ef79b7..64018e8236b2824 100644
--- a/clang/test/Driver/haiku.cpp
+++ b/clang/test/Driver/haiku.cpp
@@ -1,5 +1,5 @@
 // Check the C++ header path (libstdc++)
-// RUN: %clangxx --target=x86_64-unknown-haiku -### %s 2>&1 \
+// RUN: %clangxx --target=x86_64-unknown-haiku --stdlib=libstdc++ -### %s 2>&1 \
 // RUN:   --sysroot=%S/Inputs/haiku_x86_64_tree \
 // RUN:   | FileCheck --check-prefix=CHECK-LIBSTDCXX-HEADER-PATH %s
 // CHECK-LIBSTDCXX-HEADER-PATH: "-internal-isystem" "[[SYSROOT:[^"]+]]/boot/system/develop/headers/c++"