[clang-repl] Improve flags responsible for generating shared wasm binaries (#116735)

There are a couple changes in this PR that help getting clang-repl to
run in the browser. Using a jupyterlite instance for the example pasted
below

1) Updating flags responsible for generating shared wasm binaries that
need to be dynamically loaded Most Importantly as can be seen in the
changes `shared` and `allow-undefined` are crucial.



![image](https://github.com/user-attachments/assets/1183fd44-8951-496a-899a-e4af39a48447)

2) While exiting we encounter this.



![image](https://github.com/user-attachments/assets/9487a3f4-7200-471d-ba88-09e98ccbc47a)


Now as can be seen here 


https://github.com/llvm/llvm-project/blob/cd418030de7ae75750bc4e48d1238baf03c675e5/clang/lib/Interpreter/Interpreter.cpp#L421-L430

We call cleanUP in the destructor. Now cleanUP through
IncrementalExecutor tries to deinitialize the JIT which wasn't even
intialized as runCtors in wasm.cpp is a no-op


https://github.com/llvm/llvm-project/blob/cd418030de7ae75750bc4e48d1238baf03c675e5/clang/lib/Interpreter/IncrementalExecutor.cpp#L94-L101


https://github.com/llvm/llvm-project/blob/cd418030de7ae75750bc4e48d1238baf03c675e5/clang/lib/Interpreter/Wasm.cpp#L107-L109

1 files changed, 0 insertions, 1 deletions

diff --git a/clang/lib/Interpreter/Interpreter.cpp b/clang/lib/Interpreter/Interpreter.cpp
index bc96da8..73ad766 100644
--- a/clang/lib/Interpreter/Interpreter.cpp
+++ b/clang/lib/Interpreter/Interpreter.cpp
@@ -196,7 +196,6 @@ IncrementalCompilerBuilder::CreateCpp() {
 #ifdef __EMSCRIPTEN__
   Argv.push_back("-target");
   Argv.push_back("wasm32-unknown-emscripten");
-  Argv.push_back("-pie");
   Argv.push_back("-shared");
 #endif
   Argv.insert(Argv.end(), UserArgs.begin(), UserArgs.end());