[clang-repl] Fix undefined lld::wasm::link symbol while building clangInterpreter...

While building llvm (clang, lld) for wasm using emscripten (recipe
hosted on emscripten-forge
https://github.com/emscripten-forge/recipes/tree/main/recipes/recipes_emscripten/llvm)
I ended up with this error
```
 │ │ wasm-ld: error: ../../../../lib/libclangInterpreter.a(Wasm.cpp.o): undefined symbol: lld::wasm::link(llvm::ArrayRef<char const*>, llvm::raw_ostream&, llvm:
 │ │ :raw_ostream&, bool, bool)
 ```
 This is due to the link function here
 https://github.com/llvm/llvm-project/blob/a4819bd46d8baebc3aaa8b38f78065de33593199/clang/lib/Interpreter/Wasm.cpp#L25-L30

 This was added through this PR (https://github.com/llvm/llvm-project/pull/86402) as an attempt to support running clang-repl and executing C++ code interactively inside a Javascript engine using WebAssembly when built with Emscripten.

 The definition for link is present in lldwasm and when building for the emscripten platform we should be linking against it.

(cherry picked from commit 075581f34035c01659cc883d0d69336c279ef0d5)

diff --git a/clang/lib/Interpreter/CMakeLists.txt b/clang/lib/Interpreter/CMakeLists.txt
index 6a069659ebb8dbad25c737f9941019fb55a0783c..0a2d60757c216d78d66f45eb4133895f4ec39aa1 100644 (file)
--- a/clang/lib/Interpreter/CMakeLists.txt
+++ b/clang/lib/Interpreter/CMakeLists.txt
@@ -14,6 +14,7 @@ set(LLVM_LINK_COMPONENTS
 
 if (EMSCRIPTEN AND "lld" IN_LIST LLVM_ENABLE_PROJECTS)
   set(WASM_SRC Wasm.cpp)
+  set(WASM_LINK lldWasm)
 endif()
 
 add_clang_library(clangInterpreter
@@ -43,6 +44,7 @@ add_clang_library(clangInterpreter
   clangParse
   clangSema
   clangSerialization
+  ${WASM_LINK}
   )
 
 if ((MINGW OR CYGWIN) AND BUILD_SHARED_LIBS)