CMAKE - Fix ABSL in clang18+ (#106)

Please see:
- https://github.com/abseil/abseil-cpp/issues/1747
- https://github.com/llvm/llvm-project/issues/102443

When GRPC is compiled with different compiler from RDC - ABI broke.
Possibly because some templates were not instantiated.
Setting '-fclang-abi-compat=17' fixes the issue.

Change-Id: Ic6409cf413c87b135f334e5b03145cb1c63356d4

Signed-off-by: Galantsev, Dmitrii <dmitrii.galantsev@amd.com>

[ROCm/rdc commit: a8d479c147]

projects/rdc/README.md

@@ -70,6 +70,7 @@ Below example installs gRPC into `/opt/grpc`
         -DgRPC_INSTALL=ON \
         -DgRPC_BUILD_TESTS=OFF \
         -DBUILD_SHARED_LIBS=ON \
+        -DCMAKE_SHARED_LINKER_FLAGS_INIT=-Wl,--enable-new-dtags,--build-id=sha1,--rpath,'$ORIGIN' \
         -DCMAKE_INSTALL_PREFIX="$GRPC_ROOT" \
         -DCMAKE_INSTALL_LIBDIR=lib \
         -DCMAKE_BUILD_TYPE=Release

projects/rdc/server/CMakeLists.txt

@@ -48,6 +48,16 @@ else()
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -ggdb -O0 -DDEBUG")
 endif()
 
+# Issue with ABI compatibility and gRPC.
+# See:
+# - https://github.com/llvm/llvm-project/issues/102443
+# - https://github.com/abseil/abseil-cpp/issues/1747
+if(CMAKE_CXX_COMPILER_ID STREQUAL "Clang" AND CMAKE_CXX_COMPILER_VERSION VERSION_GREATER_EQUAL 18.0.0)
+    message("Compiler is " ${CMAKE_CXX_COMPILER_ID} ":" ${CMAKE_CXX_COMPILER_VERSION})
+    message("Applying abi patch...")
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fclang-abi-compat=17")
+endif()
+
 set(SRC_DIR "src")
 set(INC_DIR "include/rdc")