[PATCH v2] rust: Use libc++ runtime when using clang with llvm runtime

[Khem Raj <raj.khem@gmail.com>]

meta-clang has options when it comes to C++ runtime, default is to use
gnu runtime, other options are llvm runtime and android runtime. This
patch helps when a distro is using llvm runtime for C/C++ runtime. It
informs the rust build system about right C++ runtime to configure for
when such a setting is used.

Signed-off-by: Khem Raj <raj.khem@gmail.com>
---
v2: Rebase now that 1.63 is in

 meta/recipes-devtools/rust/rust.inc | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/meta/recipes-devtools/rust/rust.inc b/meta/recipes-devtools/rust/rust.inc
index 284347dedc..3a7b993ee8 100644
--- a/meta/recipes-devtools/rust/rust.inc
+++ b/meta/recipes-devtools/rust/rust.inc
@@ -107,6 +107,8 @@ python do_configure() {
     # [llvm]
     config.add_section("llvm")
     config.set("llvm", "static-libstdcpp", e(False))
+    if "llvm" in (d.getVar('RUNTIME', True) or ""):
+        config.set("llvm", "use-libcxx", e(True))
 
     # [rust]
     config.add_section("rust")
-- 
2.37.3