build: with -DCLANGD_ENABLE_REMOTE=ON, search for grpc++ dependencies too

[sylvestre.ledru]

Summary

Fixes: https://github.com/llvm/llvm-project/issues/59844

[serge-sans-paille]

cmake/Modules/FindGRPC.cmake

85

Shouldn't this be ${GPRC_OPTS}?

95

same here

100

and here?

[sylvestre.ledru]

add the missing {}

[serge-sans-paille]

LGTM, assuming, you actually tested that locally.

[kadircet]

clang/cmake/modules/AddGRPC.cmake

7

Hi @sylvestre.ledru this seem to have broken clangd bots (also doesn't work for local dev environment anymore) https://lab.llvm.org/buildbot/#/builders/131/builds/38935 (buildbot was broken before that for a different reason).

I believe the issue is because you're looking for gpr/grpc only in the absence of target grpc++, but in other setups, e.g. the one used by buildbot and the only one supported in theory, that uses grpc build from sources. You can find a repro setup in details here https://github.com/clangd/clangd/blob/master/.github/workflows/autobuild.yaml#L206. Required configuration for LLVM looks like:
cmake -G Ninja ../llvm/ -DCMAKE_BUILD_TYPE=RELEASE -DLLVM_ENABLE_PROJECTS="clang;clang-tools-extra" -DCLANGD_ENABLE_REMOTE=1 -DGRPC_INSTALL_PATH=$HOME/.local (assuming you run grpc installation to $HOME/.local).

I'll revert to unblock development (and to be able to investigate the other issue on the build bot).

[sylvestre.ledru]

thanks. reverting is fine :)

clang/cmake/modules/AddGRPC.cmake

 include(FindGRPC)
 
 function(generate_clang_protos_library LibraryName ProtoFile)
   # Take the first two args and forward the remaining to generate_proto_sources.
   cmake_parse_arguments(PARSE_ARGV 2 PROTO "" "" "")
   generate_proto_sources(ProtoSource ${ProtoFile} ${PROTO_UNPARSED_ARGUMENTS})
+  set(LINKED_GRPC_LIBRARIES protobuf gpr grpc grpc++)
 
+  if (ABSL_SYNCHRONIZATION_LIBRARY)
+    list(APPEND LINKED_GRPC_LIBRARIES absl_synchronization)
+  endif()
   add_clang_library(${LibraryName} ${ProtoSource}
     PARTIAL_SOURCES_INTENDED
-    LINK_LIBS PUBLIC grpc++ protobuf)
+    LINK_LIBS PUBLIC  ${LINKED_GRPC_LIBRARIES})
+
 endfunction()

cmake/Modules/FindGRPC.cmake

if (HOMEBREW)
         list(APPEND PROTOBUF_OPTS PATHS ${PROTOBUF_HOMEBREW_PATH}/lib NO_DEFAULT_PATH)
       endif()
       if (ABSL_HOMEBREW_RETURN_CODE EQUAL "0")
         list(APPEND GRPC_INCLUDE_PATHS ${ABSL_HOMEBREW_PATH}/include)
       endif()
     endif()
   endif()
   if(NOT TARGET grpc++)
+    find_library(GPR_LIBRARY gpr ${GRPC_OPTS} REQUIRED)
+    add_library(gpr UNKNOWN IMPORTED GLOBAL)
+    message(STATUS "Using gpr: " ${GPR_LIBRARY})
+    set_target_properties(gpr PROPERTIES IMPORTED_LOCATION ${GPR_LIBRARY})
+
     find_library(GRPC_LIBRARY grpc++ ${GRPC_OPTS} REQUIRED)
     add_library(grpc++ UNKNOWN IMPORTED GLOBAL)
     message(STATUS "Using grpc++: " ${GRPC_LIBRARY})
     set_target_properties(grpc++ PROPERTIES IMPORTED_LOCATION ${GRPC_LIBRARY})
     target_include_directories(grpc++ INTERFACE ${GRPC_INCLUDE_PATHS})
+    find_library(GRPC2_LIBRARY grpc ${GRPC_OPTS} REQUIRED)
+    add_library(grpc UNKNOWN IMPORTED GLOBAL)
+    message(STATUS "Using grpc: " ${GRPC2_LIBRARY})
+    set_target_properties(grpc PROPERTIES IMPORTED_LOCATION ${GRPC2_LIBRARY})
+
+    find_library(ABSL_SYNCHRONIZATION_LIBRARY absl_synchronization ${GRPC_OPTS} QUIET)
+    if (ABSL_SYNCHRONIZATION_LIBRARY)
+      add_library(absl_synchronization UNKNOWN IMPORTED GLOBAL)
+      message(STATUS "Using absl_synchronization: " ${ABSL_SYNCHRONIZATION_LIBRARY})
+      set_target_properties(absl_synchronization PROPERTIES IMPORTED_LOCATION ${ABSL_SYNCHRONIZATION_LIBRARY})
+    endif()
+
     if (ENABLE_GRPC_REFLECTION)
       find_library(GRPC_REFLECTION_LIBRARY grpc++_reflection ${GRPC_OPTS} REQUIRED)
       add_library(grpc++_reflection UNKNOWN IMPORTED GLOBAL)
       set_target_properties(grpc++_reflection PROPERTIES IMPORTED_LOCATION ${GRPC_REFLECTION_LIBRARY})
     endif()
     find_library(PROTOBUF_LIBRARY protobuf ${PROTOBUF_OPTS} REQUIRED)
     message(STATUS "Using protobuf: " ${PROTOBUF_LIBRARY})
     add_library(protobuf UNKNOWN IMPORTED GLOBAL)