fix(compiler): Type inference rewriter: Fix use-after-free in functio…

…n renaming

The type inference rewriter changes the name of the rewritten function
to the name of the original function when the rewriting process is
complete. However, the name is retrieved from the original function
operation after the operation has already been replaced and thus
destroyed, resulting in a null pointer dereference.

This change retrieves the name of the original function before it is
replaced and saves it in a copy, which is then used to safely assign
the new name to the rewritten function.

compilers/concrete-compiler/compiler/include/concretelang/Transforms/TypeInferenceRewriter.h

@@ -125,8 +125,9 @@ class TypeInferenceRewriter {
 
     // Replace original function and remove suffix from the name of the new
     // function
+    std::string oldFuncName = func.getName().str();
     rewriter.replaceOp(func, newFunc->getResults());
-    newFunc.setName(func.getName());
+    newFunc.setName(oldFuncName);
 
     return mlir::success();
   }