chore: documents why we have symbol counter in codegen.

compiler+runtime/include/cpp/jank/jit/processor.hpp

@@ -1,6 +1,7 @@
 #pragma once
 
 #include <boost/filesystem/path.hpp>
+#include <fmt/format.h>
 #include <memory>
 
 #include <clang/Interpreter/Interpreter.h>
@@ -45,7 +46,7 @@ namespace jank::jit
         return symbol.get().toPtr<T>();
       }
 
-      return err("Failed to find symbol");
+      return err(fmt::format("Failed to find the symbol: '{}'", name.c_str()));
     }
 
     result<void, native_persistent_string>

compiler+runtime/src/cpp/jank/codegen/llvm_processor.cpp

@@ -136,6 +136,17 @@ namespace jank::codegen
       auto const global_ctor_fn(ctx->global_ctor_block->getParent());
       ctx->builder->CreateCall(global_ctor_fn, {});
 
+      /* This dance is performed to keep symbol names unique across all the modules.
+       * Considering LLVM JIT symbols to be global, we need to define them with
+       * unique names to avoid conflicts during JIT recompilation/reloading.
+       *
+       * The approach, right now, is for each namespace, we will keep a counter
+       * and will increase it every time we define a new symbol. When we JIT reload
+       * the same namespace again, we will define new symbols.
+       *
+       * This IR codegen for calling `jank_ns_set_symbol_counter`, is to set the counter
+       * on intial load.
+       */
       auto const current_ns{ __rt_ctx->current_ns() };
       auto const fn_type(
         llvm::FunctionType::get(ctx->builder->getVoidTy(),

compiler+runtime/src/cpp/jank/jit/processor.cpp

@@ -195,7 +195,7 @@ namespace jank::jit
 
     if(error.isA<llvm::orc::SymbolsCouldNotBeRemoved>())
     {
-      return err(fmt::format("Failed to remove the symbol: {}", name));
+      return err(fmt::format("Failed to remove the symbol: '{}'", name));
     }
     return ok();
   }