llvm: remove LLVM_LDFLAGS from llvm-config --ldflags output

On native OE builds the LLVM_LDFLAGS gets a lot of extra flags which may
depend on exact build dir and as such be inappropriate to binaries
shared through sstate-cache. It is not possible to override this
behaviour in llvm-config since crossscripts are not being used for
native builds. Ignore LLVM_LDFLAGS for native builds.

(From OE-Core rev: a93d2bdf5c0cf1c2c08d99fd4ccd8d1aae0e0ba5)

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

2 files changed, 36 insertions, 0 deletions

diff --git a/meta/recipes-devtools/llvm/llvm/0001-llvm-config-remove-LLVM_LDFLAGS-from-ldflags-output.patch b/meta/recipes-devtools/llvm/llvm/0001-llvm-config-remove-LLVM_LDFLAGS-from-ldflags-output.patch
new file mode 100644
index 0000000000..2320399d5f
--- /dev/null
+++ b/meta/recipes-devtools/llvm/llvm/0001-llvm-config-remove-LLVM_LDFLAGS-from-ldflags-output.patch
@@ -0,0 +1,34 @@
+From caff2482f786dd7fd5f1f46f2667f7ed847cb8f8 Mon Sep 17 00:00:00 2001
+From: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
+Date: Wed, 2 Apr 2025 17:05:17 +0300
+Subject: [PATCH] llvm-config: remove LLVM_LDFLAGS from --ldflags output
+
+On native OE builds the LLVM_LDFLAGS gets a lot of extra flags which may
+depend on exact build dir and as such be inappropriate to binaries
+shared through sstate-cache. It is not possible to override this
+behaviour in llvm-config since crossscripts are not being used for
+native builds. As a OE-specific modification ignore LLVM_LDFLAGS for
+native builds.
+
+Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
+Upstream-Status: Inappropriate [OE-Specific]
+---
+ llvm/tools/llvm-config/llvm-config.cpp | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/llvm/tools/llvm-config/llvm-config.cpp b/llvm/tools/llvm-config/llvm-config.cpp
+index d5b76b1bb6c1..29f7c2eaa419 100644
+--- a/llvm/tools/llvm-config/llvm-config.cpp
++++ b/llvm/tools/llvm-config/llvm-config.cpp
+@@ -529,7 +529,7 @@ int main(int argc, char **argv) {
+         OS << ActiveIncludeOption << ' ' << LLVM_CXXFLAGS << '\n';
+       } else if (Arg == "--ldflags") {
+         OS << ((HostTriple.isWindowsMSVCEnvironment()) ? "-LIBPATH:" : "-L")
+-           << ActiveLibDir << ' ' << LLVM_LDFLAGS << '\n';
++           << ActiveLibDir << '\n';
+       } else if (Arg == "--system-libs") {
+         PrintSystemLibs = true;
+       } else if (Arg == "--libs") {
+-- 
+2.39.5
+
diff --git a/meta/recipes-devtools/llvm/llvm_20.1.2.bb b/meta/recipes-devtools/llvm/llvm_20.1.2.bb
index 0fb35a4f5b..d996a7c49c 100644
--- a/meta/recipes-devtools/llvm/llvm_20.1.2.bb
+++ b/meta/recipes-devtools/llvm/llvm_20.1.2.bb
@@ -32,6 +32,8 @@ SRC_URI[sha256sum] = "f0a4a240aabc9b056142d14d5478bb6d962aeac549cbd75b809f549924
 UPSTREAM_CHECK_URI = "https://github.com/llvm/llvm-project"
 UPSTREAM_CHECK_REGEX = "llvmorg-(?P<pver>\d+(\.\d+)+)"
 
+SRC_URI:append:class-native = " file://0001-llvm-config-remove-LLVM_LDFLAGS-from-ldflags-output.patch"
+
 S = "${WORKDIR}/llvm-project-${PV}.src"
 
 OECMAKE_SOURCEPATH = "${S}/llvm"