mesa: do not rely on native llvm-config in target sysroot

Sadly the magic is not perfect: llvm-config contains a hardcoded
value for the libdir from the native configuration, and things will
break if the target build installs libraries somewhere else (e.g. lib64).

llvm-config in target bindir also needs a rpath adjustment,
otherwise it simply won't even run when e.g. building for arm on x86.

To avoid patching llvm-source let's simply add more cases to the
llvm-config wrapper script, so that falling through to llvm-config binary
is avoided. Fortunately those cases are all static in what they return,
even though llvm-config binary does poke around the file tree to arrive
at them (which is where breakage happens if native and target don't match
exactly wrt libdir).

I verified that this works by building mesa with llvm enabled for
qemuarm64 and with baselib set to 'lib64' - so that both the target
architecture and target libdir differ from native ones.

Upstream tickets:
https://github.com/llvm/llvm-project/issues/58984
https://github.com/mesonbuild/meson/issues/11043

(From OE-Core rev: d2860e67a37623b17fc9c6e1192f06a63b7d52ff)

Signed-off-by: Alexander Kanavin <alex@linutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
(cherry picked from commit 056431883e94296b767a479d029b914392e4fd7c)
Signed-off-by: Steve Sakoman <steve@sakoman.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 9 insertions, 0 deletions

diff --git a/meta/recipes-devtools/llvm/llvm/llvm-config b/meta/recipes-devtools/llvm/llvm/llvm-config
index a45f38c650..5e4ded2da5 100644
--- a/meta/recipes-devtools/llvm/llvm/llvm-config
+++ b/meta/recipes-devtools/llvm/llvm/llvm-config
@@ -29,6 +29,15 @@ for arg in "$@"; do
     --ldflags)
       output="${output} ${LDFLAGS}"
       ;;
+    --shared-mode)
+      output="${output} shared"
+      ;;
+    --libs)
+      output="${output} -lLLVM"
+      ;;
+    --link-shared)
+      break
+      ;;
     *)
       remain="${remain} ${arg}"
       ;;